Testing Reed Muller Codes ∗ (2009)
Noga Alon, Tali Kaufman, Michael Krivelevich, Simon Litsyn, Dana Ron
A code is locally testable if there is a way to indicate with high probability that a vector is far enough from any codeword by accessing only a very small number of the vector’s bits. We show that...
On smoothed k-CNF formulas and the Walksat algorithm (2009)
Amin Coja-oghlan, Uriel Feige, Alan Frieze, Michael Krivelevich, Dan Vilenchik
In this paper we study the model of ε-smoothed k-CNF formulas. Starting from an arbitrary instance F with n variables and m = dn clauses, apply the ε-smoothing operation of flipping the polarity of...
Michael Krivelevich, Benny Sudakov, Nicholas Wormald
induced subgraphs of a random graph
Biased positional games and small hypergraphs with large covers, submitted (2009)
Michael Krivelevich, Tibor Szabó
We prove that in the biased (1: b) Hamiltonicity and k-connectivity Maker-Breaker games (k> 0 is a constant), played on the edges of the complete graph Kn, Maker has a winning strategy for b ≤...
Hamilton cycles in highly connected and expanding graphs, submitted (2009)
Dan Hefetz, Michael Krivelevich, Tibor Szabó
graphs
Noga Alon, Ido Ben-eliezer, Michael Krivelevich
sample spaces cannot fool low degree polynomials
The critical bias for the Hamiltonicity game is n/ln n (2009)
We prove that in the biased 1:b Hamiltonicity Maker-Breaker game, played on the edges of the complete graph K_n, Maker has a winning strategy for b(n)
Spanning directed trees with many leaves (2009)
Noga Alon, Fedor V. Fomin, Gregory Gutin, Michael Krivelevich, Saket Saurabh
Abstract. The Directed Maximum Leaf Out-Branching problem is to find an out-branching (i.e. a rooted oriented spanning tree) in a given digraph with the maximum number of leaves. In this paper, we...
Ramsey games with giants (2009)
Bohman, Tom, Frieze, Alan, Krivelevich, Michael, Loh, Po-Shen, Sudakov, Benny
The classical result in the theory of random graphs, proved by Erdos and Renyi in 1960, concerns the threshold for the appearance of the giant component in the random graph process. We consider a...
Resilient pancyclicity of random and pseudo-random graphs (2009)
Krivelevich, Michael, Lee, Choongbum, Sudakov, Benny
A graph $G$ on $n$ vertices is \textit{pancyclic} if it contains cycles of length $t$ for all $3 \leq t \leq n$. In this paper we prove that for any fixed $\epsilon>0$, the random graph $G(n,p)$ with...
Hamiltonicity of the random geometric graph (2009)
Krivelevich, Michael, Muller, Tobias
Let $X_1,..., X_n$ be independent, uniformly random points from $[0,1]^2$. We prove that if we add edges between these points one by one by order of increasing edge length then, with probability...
Hamiltonicity thresholds in Achlioptas processes (2009)
Michael Krivelevich, Eyal Lubetzky, Benny Sudakov
In this paper we analyze the appearance of a Hamilton cycle in the following random process. The process starts with an empty graph on n labeled vertices. At each round we are presented with K = K(n)...
On the random satisfiable process (2009)
Michael Krivelevich, Benny Sudakov, Dan Vilenchik
Abstract. In this work we suggest a new model for generating random satisfiable k-CNF formulas. To generate such formulas – randomly permute all 2 k ` ´ n possible clauses over the variables...
Embedding nearly-spanning bounded degree trees (2009)
Noga Alon, Michael Krivelevich, Benny Sudakov
We derive a sufficient condition for a sparse graph G on n vertices to contain a copy of atreeT of maximum degree at most d on (1 − ɛ)n vertices, in terms of the expansion properties of G. As a...
Avoiding small subgraphs in Achlioptas processes, preprint (2009)
Michael Krivelevich, Po-shen Loh, Benny Sudakov
ABSTRACT: For a fixed integer r, consider the following random process. At each round, one is presented with r random edges from the edge set of the complete graph on n vertices, and is asked to...
LARGE NEARLY REGULAR INDUCED SUBGRAPHS ∗ (2009)
Noga Alon, Michael Krivelevich, Benny Sudakov
Abstract. For a real c ≥ 1 and an integer n, let f(n, c) denote the maximum integer f such that every graph on n vertices contains an induced subgraph on at least f vertices in which the maximum...
Spanning directed trees with many leaves (2009)
Noga Alon, Fedor V. Fomin, Gregory Gutin, Michael Krivelevich, Saket Saurabh
The Directed Maximum Leaf Out-Branching problem is to find an out-branching (i.e. a rooted oriented spanning tree) in a given digraph with the maximum number of leaves. In this paper, we obtain two...
MaxCut in H-free graphs (2009)
Noga Alon, Michael Krivelevich, Benny Sudakov
For a graph G, let f(G) denote the maximum number of edges in a cut of G. For an integer m and for a fixed graph H, let f(m, H) denote the minimum possible cardinality of f(G), as G ranges over all...
On smoothed k-CNF formulas and the Walksat (2009)
Amin Coja-oghlan, Uriel Feige, Alan Frieze, Michael Krivelevich, Dan Vilenchik
algorithm
A note on regular Ramsey graphs (2009)
Noga Alon, Sonny Ben-shimon, Michael Krivelevich
We prove that there is an absolute constant C> 0 so that for every natural n there exists a trianglefree regular graph with no independent set of size at least C √ n log n. 1
A note on regular Ramsey graphs (2008)
Alon, Noga, Ben-Shimon, Sonny, Krivelevich, Michael
We prove that there is an absolute constant $C>0$ so that for every natural $n$ there exists a triangle-free \emph{regular} graph with no independent set of size at least $C\sqrt{n\log n}$.
Michael Krivelevich, Benny Sudakov, Van H. Vu, Nicholas C. Wormald
the probability of independent sets in random graphs
Testing low-degree polynomials over GF(2) (2008)
Noga Alon, Tali Kaufman, Michael Krivelevich, Simon Litsyn, Dana Ron
Abstract. We describe an efficient randomized algorithm to test if a given binary function � � ����� � � ���� � is a low-degree polynomial (that is, a sum of low-degree...
Spanning directed trees with many leaves ⋆ (2008)
Noga Alon, Fedor V. Fomin, Gregory Gutin, Michael Krivelevich, Saket Saurabh
Abstract. The Directed Maximum Leaf Out-Branching problem is to find an out-branching (i.e. a rooted oriented spanning tree) in a given digraph with the maximum number of leaves. In this paper, we...
Regular induced subgraphs of a random graph (2008)
Krivelevich, Michael, Sudakov, Benny, Wormald, Nicholas
An old problem of Erd\H{o}s, Fajtlowicz and Staton asks for the order of a largest induced regular subgraph that can be found in every graph on n vertices. Motivated by this problem, we consider the...
Michael Krivelevich, Zeev Nutov, Mohammad R. Salavatipour, Jacques Verstraete, Raphael Yuster
Permission to make digital/hard copy of all or part of this material without fee for personal or classroom use provided that the copies are not made or distributed for profit or commercial advantage,...
On the random satisfiable process (2008)
Krivelevich, Michael, Sudakov, Benny, Vilenchik, Dan
In this work we suggest a new model for generating random satisfiable k-CNF formulas. To generate such formulas -- randomly permute all 2^k\binom{n}{k} possible clauses over the variables x_1, ...,...
Fast winning strategies in Avoider-Enforcer games (2008)
Hefetz, Dan, Krivelevich, Michael, Stojaković, Miloš, Szabó, Tibor
In numerous positional games the identity of the winner is easily determined. In this case one of the more interesting questions is not {\em who} wins but rather {\em how fast} can one win. These...
Hamiltonicity thresholds in Achlioptas processes (2008)
Krivelevich, Michael, Lubetzky, Eyal, Sudakov, Benny
In this paper we analyze the appearance of a Hamilton cycle in the following random process. The process starts with an empty graph on n labeled vertices. At each round we are presented with K=K(n)...
Noga Alon, Michael Krivelevich, Joel Spencer, Tibor Szabó
We investigate a game played on a hypergraph H = (V,E) bytwoplayers, Balancer and Unbalancer. They select one element of the vertex set V alternately until all vertices are selected. Balancer wins if...
Noga Alon, Michael Krivelevich, Benny Sudakov
coloring of random and pseudo-random graphs
Testing low-degree polynomials over GF(2), booktitle (2008)
Noga Alon, Tali Kaufman, Michael Krivelevich, Simon Litsyn, Dana Ron
We describe an efficient randomized algorithm to test if a given binary function f: {0, 1} n → {0, 1} is a low-degree polynomial (that is, a sum of low-degree monomials). For a given integer k ≥...
Noga Alon, Michael Krivelevich, Benny Sudakov
a large hidden clique in a random graph ∗
time has two-prover interactive protocols. Computational Complexity, 1:3–40, 1991. (2008)
Noga Alon, Tali Kaufman, Michael Krivelevich, Simon Litsyn, Dana Ron Testing, László Babai, ...
[4] Sanjeev Arora, László Babai, Jacques Stern, and Z Sweedyk. The hardness of approximate optima in lattices, codes, and systems of linear equations. Journal of
Michael Krivelevich, Benny Sudakov, Prasad Tetali
smoothed analysis in dense graphs and formulas
Abstract Testing Triangle-Freeness in General Graphs (2008)
Noga Alon, Tali Kaufman, Michael Krivelevich, Dana Ron
In this paper we consider the problem of testing whether a graph is triangle-free, and more generally, whether it is H-free, for a fixed subgraph H. The algorithm should accept graphs that are...
Noga Alon, Michael Krivelevich, Joel Spencer, Tibor Szabó
We investigate a game played on a hypergraph H = (V, E) by two players, Balancer and Unbalancer. They select one element of the vertex set V alternately until all vertices are selected. Balancer wins...
Planarity, colorability and minor games (2008)
Dan Hefetz, Michael Krivelevich, Tibor Szabó
Let m and b be positive integers and let F be a hypergraph. In an (m, b, F) Maker-Breaker game two players, called Maker and Breaker, take turns selecting previously unclaimed vertices of F. Maker...
Choosability in random hypergraphs (2008)
Michael Krivelevich, Van H. Vu
The choice number of a hypergraph H = (V, E) is the least integer s for which for every family of color lists S = {S(v) : v ∈ V}, satisfying |S(v) | = s for every v ∈ V, there exists a choice...
Vol. 19, No. 3, pp. 719–727 THE STRONG CHROMATIC INDEX OF RANDOM GRAPHS ∗ (2008)
Alan Frieze, Michael Krivelevich, Benny Sudakov
Abstract. The strong chromatic index of a graph G, denoted by χs(G), is the minimum number of colors needed to color its edges so that each color class is an induced matching. In this paper we...
Covering Codes With Improved Density (2008)
A. Blokhuis, G. D. Cohen, I. S. Honkala, S. N. Litsyn, A. C. Lobstein, ...
The ADS of the code in i) and the binary Golay code produces a ‘RSY PH“V code. This is a new code.
Avoiding small subgraphs in Achlioptas processes, preprint (2008)
Michael Krivelevich, Po-shen Loh, Benny Sudakov
Abstract For a fixed integer r, consider the following random process. At each round, one is presented with r random edges from the edge set of the complete graph on n vertices, and is asked to...
On smoothed analysis in dense graphs and formulas (2008)
Michael Krivelevich, Benny Sudakov, Prasad Tetali
ABSTRACT: We study a model of random graphs, where a random instance is obtained by adding random edges to a large graph of a given density. The research on this model has been started by Bohman and...
Testing low-degree polynomials over (2008)
Noga Alon, Tali Kaufman, Michael Krivelevich, Simon Litsyn
Abstract. We describe an efficient randomized algorithm to test if a given binary function is a low-degree polynomial (that is, a sum of low-degree monomials). For a ���� � given integer...
Algorithms with large domination ratio Noga Alon \Lambda (2008)
Gregory Gutin, Michael Krivelevich
Abstract Let P be an optimization problem, and let A be an approximation algorithm for P. The domination ratio domr(A; n) is the maximum real q such that the solution x(I) obtained by A for any...
On rainbow trees and cycles Alan Frieze (2008)
0 such that if an edge colouring of Kn is cn-bounded then there exist rainbow cycles of all sizes 3 < = k < = n.
The isoperimetric constant of the random graph process, preprint (2008)
Itai Benjamini, Simi Haber, Michael Krivelevich, Eyal Lubetzky
2\Delta graphs, where eG(0) is the edgeless graph on n vertices, and eG(t) is the result of addingan edge to e G(t- 1), uniformly distributed over all the missing edges. We show that in almost every...
Noga Alon, Michael Krivelevich, Joel Spencer, Tibor Szabó
We investigate a game played on a hypergraph H = (V,E) by two players, Balancer and Unbalancer. They select one element of the vertex set V alternately until all vertices are selected. Balancer wins...
On the random satisfiable 3CNF process (2008)
Michael Krivelevich, Benny Sudakov, Dan Vilenchik
Abstract. In this work we suggest a new model for generating random satisfiable 3CNF formulas. To generate such formulas – randomly permute all 8 � � n possible clauses over the variables...
On two Hamilton cycle problems in random graphs (2008)
Alan Frieze, Michael Krivelevich
We study two problems related to the existence of Hamilton cycles in random graphs. The first question relates to the number of edge disjoint Hamilton cycles that the random graph Gn,p contains....
On two Hamilton cycle problems in random graphs (2008)
Alan Frieze, Michael Krivelevich
1 Introduction In this paper, we give results on two problems related to Hamilton cycles in random graphs. 1.1 Edge Disjoint Hamilton Cycles It was shown by Koml'os and Szemer'edi [8] that...
Spanning directed trees with many leaves (2008)
Noga Alon, Fedor V. Fomin, Gregory Gutin, Michael Krivelevich, Saket Saurabh
Abstract. The Directed Maximum Leaf Out-Branching problem is to find an out-branching (i.e. a rooted oriented spanning tree) in a given digraph with the maximum number of leaves. In this paper, we...
Course number: 0366-3267 (2008)
Prospective audience: the course is intended for second and third year undergraduate students
Biased positional games and small hypergraphs with large covers, submitted (2008)
There are several types of positional games depending on how the identity of the winner is determined. In this paper we restrict our attention to two of them.
Avoider-Enforcer: The Rules of the Game (2008)
Dan Hefetz, Michael Krivelevich, Tibor Szabó
An Avoider-Enforcer game is played by two players, called Avoider and Enforcer, on a hypergraph F ⊆ 2 X. The players claim previously unoccupied elements of the board X in turns. Enforcer wins if...
Ido Ben-eliezer, Tali Kaufman, Michael Krivelevich, Dana Ron
the strength of query types in property testing:
Avoider-Enforcer: The Rules of the Game (2008)
Dan Hefetz, Michael Krivelevich, Tibor Szabó
An Avoider-Enforcer game is played by two players, called Avoider and Enforcer, on a hypergraph F ⊆ 2 X. The players claim previously unoccupied elements of the board X in turns. Enforcer wins if...
On smoothed k-CNF formulas and the Walksat (2008)
Amin Coja-oghlan, Uriel Feige, Alan Frieze, Michael Krivelevich, Dan Vilenchik
algorithm
Colin Cooper, Alan Frieze, Michael Krivelevich
cycles in random graphs with a
A sharp threshold for the Hamilton cycle Maker-Breaker game (2008)
Dan Hefetz, Michael Krivelevich, Tibor Szabó
We study the Hamilton cycle Maker-Breaker game, played on the edges of the random graph G(n, p). We prove a conjecture from [13], asserting that the property that Maker is able to win this game, has...
Perfectly balanced partitions of smoothed graphs (2008)
Ido Ben-eliezer, Michael Krivelevich
For a graph G = (V, E) of even order, a partition (V1, V2) of the vertices is said to be perfectly balanced if |V1 | = |V2 | and the numbers of edges in the subgraphs induced by V1 and V2 are equal....
A note on regular Ramsey graphs (2008)
Noga Alon, Sonny Ben-shimon, Michael Krivelevich
We prove that there is an absolute constant C> 0 so that for every natural n there exists a trianglefree regular graph with no independent set of size at least C √ n log n. 1
Fast winning strategies in Avoider-Enforcer games (2008)
Dan Hefetz, Michael Krivelevich, Tibor Szabó
In numerous positional games the identity of the winner is easily determined. In this case one of the more interesting questions is not who wins but rather how fast can one win. These type of...
On rainbow trees and cycles (2008)
Alan Frieze, Michael Krivelevich
We derive sufficient conditions for the existence of rainbow cycles of all lengths in edge colourings of complete graphs. We also consider rainbow colorings of a certain class of trees. 1
Sharp threshold for network reliability (2007)
Michael Krivelevich, Benny Sudakov, Van H. Vu
Given a graph G on n vertices with maximal degree d, form a random subgraph G p by choosing each edge of G independently with probability p. Strengthening a classical result of Margulis we prove that...
Noga Alon, Eldar Fischer, Michael Krivelevich, Mario Szegedy
Let P be a property of graphs. An ffl-test for P is a randomized algorithm which, given the ability to make queries whether a desired pair of vertices of an input graph G with n vertices are adjacent...
Noga Alon, Haim Kaplan, Michael Krivelevich, Dahlia Malkhi
Abstract. In this paper, we provide a method to safely store a document in perhaps the most challenging settings, a highly decentralized replicated storage system where up to half of the storage...
On A Theorem Of Lovász On Covers In r-Partite Hypergraphs (2007)
Ron Aharoni, Ron Holzman, Michael Krivelevich
. A theorem of Lov'asz asserts that ø (H)=ø (H) r=2 for every r-partite hypergraph H (where ø and ø denote the covering number and fractional covering number respectively). Here it is shown...
Adding random edges to dense graphs (2007)
Tom Bohman, Alan Frieze, Michael Krivelevich, Ryan Martin
This paper investigates the addition of random edges to arbitrary dense graphs; in particular, we determine the number of random edges required to ensure various monotone properties including the...
240 JOURNAL OF GRAPH THEORY (2007)
Noga Alon, Michael Krivelevich, Benny Sudakov
Abstract: A subgraph of a graph G is called trivial if it is either a clique or an independent set. Let qðGÞ denote the maximum number of vertices in a trivial subgraph of G. Motivated by an open...
Joel Friedman, Andreas Goerdt, Michael Krivelevich
Recognizing more unsatisable random k-SAT instances eciently
Noga Alon, Michael Krivelevich
A graph G is called k-saturated, where k 3 is an integer, if G is K k
graphs without short cycles (2007)
Noga Alon, Béla Bolloba S, Michael Krivelevich, Benny Sudakov E
Maximum cuts and judicious partitions in
Noga Alon, Michael Krivelevich, Benny Sudakov
It is shown that the chromatic number of any graph with maximum degree d in which the number of edges in the induced subgraph on the set of all neighbors of any vertex does not exceed d
Michael Krivelevich, Benny Sudakov, Van H. Vu, Nicholas C. Wormald
Let k be the asymptotic value of the independence number of the random graph G(n; p). We prove that if the edge probability p(n) satises p(n) n
Michael Krivelevich, Benny Sudakov
We show that if the second largest absolute value of an eigenvalue of a d-regular graph G on n vertices is at most cd 3
Sharp thresholds for certain Ramsey properties of random graphs (2007)
Ehud Friedgut, Michael Krivelevich
In a series of papers culminating in [11] Rodl, Rucinski and others study the thresholds of Ramsey properties of random graphs i.e. for a given graph H, when does a random graph almost surely have...
Sharp threshold for network reliability (2007)
Michael Krivelevich, Benny Sudakov, Van H. Vu
Given a graph G on n vertices with average degree d, form a random subgraph G p by choosing each edge of G independently with probability p. Strengthening a classical result of Margulis we prove that...
Sparse pseudo-random graphs are Hamiltonian (2007)
Michael Krivelevich, Benny Sudakov
In this paper we study Hamilton cycles in sparse pseudo-random graphs. We prove that if the second largest absolute value of an eigenvalue of a d-regular graph G on n vertices satises (log log n) 2...
Choosability in random hypergraphs (2007)
Michael Krivelevich, Van H. Vu
The choice number of a hypergraph H = (V; E) is the least integer s for which for every family of color lists S = fS(v) : v 2 V g, satisfying jS(v)j = s for every v 2 V, there exists a choice...
Noga Alon, Michael Krivelevich, Benny Sudakov
We consider the following probabilistic model of a graph on n labeled vertices. First choose a random graph G(n; 1=2) and then choose randomly a subset Q of vertices of size k and force it to be a...
Michael Krivelevich, Benny Sudakov, Van H. Vu, Nicholas C. Wormald
Let k be the asymptotic value of the independence number of the random graph G(n; p). We prove that if the edge probability p(n) satises p(n) n
Michael Krivelevich, Benny Sudakov, Van H. Vu, Nicholas C. Wormald
Random d-regular graphs have been well studied when d is xed and the number of vertices goes to innity. We obtain results on many of the properties of a random d-regular graph when d = d(n) grows...
Noga Alon, Michael Krivelevich, Paul Seymour
It is shown that any k-critical graph with n vertices contains a cycle of length at least 2
Michael Krivelevich, Beverly Sackler, Faculty Exact Sciences
Almost perfect matchings in random uniform
Noga Alon, Haim Kaplan, Michael Krivelevich, Dahlia Malkhi
Abstract. In this paper, we provide a method to safely store a document in perhaps the most challenging settings, a highly decentralized replicated storage system where up to half of the storage...
Department of Mathematics, (2007)
A graph G is k-critical if it has chromatic number k, but every proper subgraph of it is (k 1)-colorable. This paper is devoted to investigating the following question: for given k and n, what is the...
mkrivel@math.ias.edu. Research supported by an IAS/DIMACS Postdoctoral (2007)
Michael Krivelevich, Benny Sudakov
(Extended abstract)
Hamilton Cycles in Random Subgraphs of Pseudo-Random Graphs Alan Frieze (2007)
Given an r-regular graph G on n vertices with a Hamilton cycle, order its edges randomly and insert them one by one according to the chosen order, starting from the empty graph. We prove that if the...
Abstract. The main result of this paper is that for every 2 r and n suf-ciently large there exist graphs of order n, not containing a complete graph on s vertices, in which every relatively not too...
for all (x 1; : : : ; xn) 2 S. The width of a function f j is dened as (2007)
Ron Aharoni, Ron Holzman, Michael Krivelevich, Roy Meshulam
Abstract. In 1950 Bang proposed a conjecture which became known as \the plank conjecture": Suppose that a convex set S contained in the unit cube of
Sharp Thresholds for Ramsey Properties of Random Graphs. (2007)
Ehud Friedgut, Michael Krivelevich
In a series of papers culminating in [11] Rodl, Ruci'nski and others study the thresholds of Ramsey properties of random graphs and hypergraphs, i.e. for a given graph H, when does a random...
Noga Alon, Eldar Fischer, Michael Krivelevich, Mario Szegedy
Let P be a property of graphs. An -test for P is a randomized algorithm which, given the ability to make queries whether a desired pair of vertices of an input graph G with n vertices are adjacent or...
Sparse pseudo-random graphs are Hamiltonian (2007)
Michael Krivelevich, Benny Sudakov
In this paper we study Hamilton cycles in sparse pseudo-random graphs. We prove that if the second largest absolute value of an eigenvalue of a d-regular graph G on n vertices satises (log log n)
Noga Alon, Michael Krivelevich, Benny Sudakov
We consider the following probabilistic model of a graph on n labeled vertices. First choose a random graph G(n; 1=2) and then choose randomly a subset Q of vertices of size k and force it to be a...
Michael Krivelevich, Van H. Vu
Approximating the independence number and the chromatic number in expected polynomial time
Dimitris Achlioptas, Jeong Han Kim, Michael Krivelevich, Prasad Tetali
A 2-coloring of a hypergraph is a mapping from its vertex set to a set of two colors such that no edge is monochromatic. Let H = H(k; n; p) be a random k-uniform hypergraph on a vertex set V of...
Department of Mathematics, (2007)
The weighted set covering problem, restricted to the class of r-uniform hypergraphs, is considered. We propose a new approach, based on a recent result of Aharoni, Holzman and Krivelevich about the...
Noga Alon, Michael Krivelevich, Simon Litsyn
hashing and applications to digital ngerprinting
Hamilton Cycles in Random Subgraphs of Pseudo-Random Graphs Alan Frieze (2007)
Given an r-regular graph G on n vertices with a Hamilton cycle, order its edges randomly and insert them one by one according to the chosen order, starting from the empty graph. We prove that if the...
Michael Krivelevich, Benny Sudakov
We show that if the second largest absolute value of an eigenvalue of a d-regular graph G on n vertices is at most cd 3
On the Probability of Independent Sets in Random Graphs (2007)
Michael Krivelevich, Benny Sudakov, Van H. Vu, Nicholas C. Wormald
Let k be the asymptotic value of the independence number of the random graph G(n; p). We prove that if the edge probability p(n) satis es p(n) n n then the probability that G(n; p) does not contain...
On the Probability of Independent Sets in Random Graphs (2007)
Michael Krivelevich, Benny Sudakov, Van H. Vu, Nicholas C. Wormald
Let k be the asymptotic value of the independence number of the random graph G(n, p). We prove that if the edge probability p(n) satisfies p(n) n -2/5 ln n then the probability that c, for some...
Bounding Ramsey numbers through large (2007)
Deviation Inequalities Michael, Michael Krivelevich
We develop a new approach for proving lower bounds for various Ramsey numbers, based on using large deviation inequalities. This approach enables us to obtain the bounds for the o-diagonal Ramsey );...
Covering Codes with Improved Density (2007)
Michael Krivelevich, Benny Sudakov, Van H. Vu
We prove a general recursive inequality concerning (R), the asymptotic (worst) density of the best binary covering codes of radius R. In particular, this inequality implies that (R) e (R log R+ log...
Turán numbers of bipartite graphs and related Ramsey-type questions (2007)
Noga Alon, Michael Krivelevich, Benny Sudakov
For a graph H and an integer n, the Turan number ex(n; H) is the maximum possible number of edges in a simple graph on n vertices that contains no copy of H . H is r-degenerate if every subgraph of...
Abraham D. Flaxman, Michael Krivelevich
It is known [6] that if the edge costs of the complete graph K n are independent random variables, uniformly distributed between 0 and 1, then the expected cost of the minimum spanning tree is...
Almost universal graphs Alan Frieze (2007)
We study the question as to when a random graph with n vertices and m edges contains a copy of almost all graphs with n vertices and cn=2 edges, c constant. We identify a "phase transition...
Vertex Percolation on Expander Graphs (2007)
Ben-Shimon, Sonny, Krivelevich, Michael
We say that a graph $G=(V,E)$ on $n$ vertices is a $\beta$-expander for some constant $\beta>0$ if every $U\subseteq V$ of cardinality $|U|\leq \frac{n}{2}$ satisfies $|N_G(U)|\geq \beta|U|$ where...
Large nearly regular induced subgraphs (2007)
Alon, Noga, Krivelevich, Michael, Sudakov, Benny
For a real c \geq 1 and an integer n, let f(n,c) denote the maximum integer f so that every graph on n vertices contains an induced subgraph on at least f vertices in which the maximum degree is at...
Avoiding small subgraphs in Achlioptas processes (2007)
Krivelevich, Michael, Loh, Po-Shen, Sudakov, Benny
For a fixed integer r, consider the following random process. At each round, one is presented with r random edges from the edge set of the complete graph on n vertices, and is asked to choose one of...
Better Algorithms and Bounds for Directed Maximum Leaf Problems (2007)
Alon, Noga, Fomin, Fedor V., Gutin, Gregory, Krivelevich, Michael, Saurabh, Saket
The {\sc Directed Maximum Leaf Out-Branching} problem is to find an out-branching (i.e. a rooted oriented spanning tree) in a given digraph with the maximum number of leaves. In this paper, we...
Minors in expanding graphs (2007)
Krivelevich, Michael, Sudakov, Benny
Extending several previous results we obtained nearly tight estimates on the maximum size of a clique-minor in various classes of expanding graphs. These results can be used to show that graphs...
Embedding nearly-spanning bounded degree trees (2007)
Alon, Noga, Krivelevich, Michael, Sudakov, Benny
We derive a sufficient condition for a sparse graph G on n vertices to contain a copy of a tree T of maximum degree at most d on (1-\epsilon)n vertices, in terms of the expansion properties of G. As...
Parameterized Algorithms for Directed Maximum Leaf Problems (2007)
Alon, Noga, Fomin, Fedor, Gutin, Gregory, Krivelevich, Michael, Saurabh, Saket
We prove that finding a rooted subtree with at least $k$ leaves in a digraph is a fixed parameter tractable problem. A similar result holds for finding rooted spanning trees with many leaves in...
Why almost all k-colorable graphs are easy to color (2007)
Amin Coja-oghlan, Michael Krivelevich, Dan Vilenchik
Coloring a k-colorable graph using k colors (k ≥ 3) is a notoriously hard problem. Considering average case analysis allows for better results. In this work we consider the uniform distribution...
Better Algorithms and Bounds for Directed Maximum Leaf Problems (2007)
Noga Alon, Fedor V. Fomin, Gregory Gutin, Michael Krivelevich, Saket Saurabh
Abstract. The Directed Maximum Leaf Out-Branching problem is to find an out-branching (i.e. a rooted oriented spanning tree) in a given digraph with the maximum number of leaves. In this paper, we...
Why almost all k-CNF formulas are easy (2007)
Amin Coja-oghlan, Michael Krivelevich, Dan Vilenchik
Abstract. Finding a satisfying assignment for a k-CNF formula (k ≥ 3), assuming such exists, is a notoriously hard problem. In this work we consider the uniform distribution over satisfiable k-CNF...
Parameterized Algorithms for Directed Maximum Leaf Problems (2007)
Noga Alon, Fedor V. Fomin, Gregory Gutin, Michael Krivelevich, Saket Saurabh
Abstract. We prove that finding a rooted subtree with at least k leaves in a digraph is a fixed parameter tractable problem. A similar result holds for finding rooted spanning trees with many leaves...
Parameterized Algorithms for Directed Maximum Leaf Problems (2007)
Noga Alon, Fedor V. Fomin, Gregory Gutin, Michael Krivelevich, Saket Saurabh
We prove that finding a rooted subtree with at least k leaves in a directed graph is a fixed parameter tractable problem. A similar result holds for finding rooted spanning trees with many leaves in...
Approximation Algorithms and Hardness Results for Cycle Packing Problems (2007)
Michael Krivelevich, Zeev Nutov, Mohammad R. Salavatipour, Jacques Yuster, Raphael Yuster
Vertex Percolation on Expander Graphs (2007)
Sonny Ben-shimon, Michael Krivelevich
We say that a graph G = (V, E) on n vertices is a β-expander for some constant β> 0 if every U ⊆ V of cardinality |U | ≤ n 2 satisfies |NG(U) | ≥ β|U | where NG(U) denotes the...
On unbiased games on random graphs (2007)
Dan Hefetz, Michael Krivelevich, Tibor Szabó, H ⊆h
We study unbiased Maker-Breaker positional games played on the edges of the random graph G(n, p). As the main result of the paper, we prove a conjecture from [18], that the property that Maker is...
Fast winning strategies in positional games (2007)
Dan Hefetz, Michael Krivelevich, Tibor Szabó
For the unbiased Maker-Breaker game, played on the hypergraph H, let τM(H) be the smallest integer t such that Maker can win the game within t moves (if the game is a Breaker’s win then set τM(H)...
Parameterized Algorithms for Directed Maximum Leaf Problems (2007)
Noga Alon, Fedor V. Fomin, Gregory Gutin, Michael Krivelevich, Saket Saurabh, Royal Holloway
D is an out-tree if T is an oriented tree with only one vertex s of in-degree zero (called the root). The vertices of
Parameterized Algorithms for Directed Maximum Leaf Problems (2007)
Noga Alon, Noga Alon, Fedor V. Fomin, Fedor V. Fomin, Gregory Gutin, Gregory Gutin, ...
We prove that finding a rooted subtree with at least k leaves in a digraph is a fixed parameter tractable problem. A similar result holds for finding rooted spanning trees with many leaves in...
Small sample spaces cannot fool low degree polynomials Extended Abstract (2007)
Noga Alon, Ido Ben-eliezer, Michael Krivelevich
A distribution D on a set S ⊂ {0, 1} N ɛ-fools polynomials of degree at most d in N variables over Z2 if for any such polynomial P, the probability that P (x) vanishes when x is chosen according...
Better Algorithms and Bounds for Directed Maximum Leaf Problems (2007)
Noga Alon, Fedor V. Fomin, Gregory Gutin, Michael Krivelevich, Saket Saurabh, Royal Holloway
Abstract. The Directed Maximum Leaf Out-Branching problem is to find an out-branching (i.e. a rooted oriented spanning tree) in a given digraph with the maximum number of leaves. In this paper, we...
Equitable coloring of random graphs (2007)
Michael Krivelevich, Balázs Patkós
An equitable coloring of a graph is a proper vertex coloring such that the sizes of any two color classes differ by at most one. The least positive integer k for which there exists an equitable...
Why almost all k-colorable graphs are easy to color (2007)
Amin Coja-oghlan, Michael Krivelevich, Dan Vilenchik
Abstract Coloring a k-colorable graph using k colors (k> = 3) is a notoriously hard problem. Consideringaverage case analysis allows for better results. In this work we consider the uniform...
Hamilton cycles in highly connected and expanding graphs (2006)
Hefetz, Dan, Krivelevich, Michael, Szabo, Tibor
In this paper we prove a sufficient condition for the existence of a Hamilton cycle, which is applicable to a wide variety of graphs, including relatively sparse graphs. In contrast to previous...
Solving random satisfiable 3CNF formulas in expected polynomial time (2006)
Michael Krivelevich, Dan Vilenchik
We present an algorithm for solving 3SAT instances. Several algorithms have been proved to work whp (with high probability) for various SAT distributions. However, an algorithm that works whp has a...
Michael Krivelevich, Benny Sudakov
Random graphs have proven to be one of the most important and fruitful concepts in modern Combinatorics and Theoretical Computer Science. Besides being a fascinating study subject for their own sake,...
On the chromatic number of random graphs with a fixed (2006)
Alan Frieze, Michael Krivelevich, Cliff Smyth
degree sequence
Solving random satisfiable 3CNF formulas in expected polynomial time (2006)
Michael Krivelevich, Dan Vilenchik
1 Introduction and Results 1.1 The Planted 3SAT Distribution A 3CNF for-mula over the variables x1, x2,..., xn is a conjunction ofclauses C1, C2,..., Cm where each clause is a disjunctionof three...
Testing triangle-freeness in general graphs (2006)
Noga Alon, Tali Kaufman, Michael Krivelevich, Dana Ron
In this paper we consider the problem of testing whether a graph is triangle-free, and more generally, whether it is H-free, for a fixed subgraph H. The algorithm should accept graphs that are...
Testing triangle-freeness in general graphs (2006)
Noga Alon, Tali Kaufman, Michael Krivelevich, Dana Ron
In this paper we consider the problem of testing whether a graph is triangle-free, and more generally, whether it is H-free, for a fixed subgraph H. The algorithm should accept graphs that are...
Colouring complete bipartite graphs from random lists, Random Structures and Algorithms 29 (2006)
Michael Krivelevich, Asaf Nachmias
Abstract Let Kn,n be the complete bipartite graph with n vertices in each side. For each vertex drawuniformly at random a list of size k from a base set S of size s = s(n). In this paper we...
Semirandom models as benchmarks for coloring algorithms (2006)
Michael Krivelevich, Dan Vilenchik
Abstract Semirandom models generate problem instances by blend-ing random and adversarial decisions, thus intermediating between the worst-case assumptions that may be overly pes-simistic in many...
Random regular graphs of non-constant degree: edge distribution and applications (2006)
Sonny Ben-shimon, Michael Krivelevich
edges and applications
Random regular graphs of non-constant degree: edge distribution and applications (2006)
Sonny Ben-shimon, Michael Krivelevich
In this work we show that with high probability the chromatic number of a graph sampled from the random regular graph model Gn,d for d = o(n 1/5) is concentrated in two consecutive values, thus...
Colouring complete bipartite graphs from random lists (2005)
Krivelevich, Michael, Nachmias, Asaf
Let $K_{n,n}$ be the complete bipartite graph with $n$ vertices in each side. For each vertex draw uniformly at random a list of size $k$ from a base set $S$ of size $s=s(n)$. In this paper we...
Colouring powers of cycles from random lists (2005)
Krivelevich, Michael, Nachmias, Asaf
Let $C_n^k$ be the $k$-th power of a cycle on $n$ vertices (i.e. the vertices of $C_n^k$ are those of the $n$-cycle, and two vertices are connected by an edge if their distance along the cycle is at...
Random regular graphs of non-constant degree: Concentration of the chromatic number (2005)
Ben-Shimon, Sonny, Krivelevich, Michael
In this work we show that with high probability the chromatic number of a graph sampled from the random regular graph model $\Gnd$ for $d=o(n^{1/5})$ is concentrated in two consecutive values, thus...
The isoperimetric constant of the random graph process (2005)
Benjamini, Itai, Haber, Simi, Krivelevich, Michael, Lubetzky, Eyal
The isoperimetric constant of a graph $G$ on $n$ vertices, $i(G)$, is the minimum of $\frac{|\partial S|}{|S|}$, taken over all nonempty subsets $S\subset V(G)$ of size at most $n/2$, where $\partial...
Krivelevich, Michael, Sudakov, Benny
Random graphs have proven to be one of the most important and fruitful concepts in modern Combinatorics and Theoretical Computer Science. Besides being a fascinating study subject for their own sake,...
Almost universal graphs (2005)
Alan Frieze, Michael Krivelevich
We study the question as to when a random graph with n vertices and m edges contains a copy of almost all graphs with n vertices and cn/2 edges, c constant. We identify a ”phase transition ” at c...
Almost universal graphs (2005)
Alan Frieze, Michael Krivelevich
We study the question as to when a random graph with n vertices and m edges contains a copy of almost all graphs with n vertices and cn/2 edges, c constant. We identify a ”phase transition ” at c...
Bart- Moe games, JumbleG and Discrepancy (2005)
Dan Hefetz, Michael Krivelevich, Tibor Szabó
Let A and B be hypergraphs with a common vertex set V. In a (p, q, A ∪ B) Bart-Moe game, the players take turns selecting previously unclaimed vertices of V. The game ends when every vertex has...
The Raymond, Beverly Sackler, Faculty Exact Sciences, Tali Kaufman, Under Professors, Noga Alon, ...
Property Testing is nowadays one of the central fields in Theoretical Computer Science. This concept played a major role in the proof of the celebrated PCP theorem. A typical task in Property Testing...
On the asymptotic value of the choice number of complete multi-partite graphs (2004)
Gazit, Nurit, Krivelevich, Michael
We calculate the asymptotic value of the choice number of complete multi-partite graphs.
A Lower Bound on the Density of Sphere Packings via Graph Theory (2004)
Krivelevich, Michael, Litsyn, Simon, Vardy, Alexander
Using graph-theoretic methods we give a new proof that for all sufficiently large $n$, there exist sphere packings in $\R^n$ of density at least $cn2^{-n}$, exceeding the classical Minkowski bound by...
Tight Bounds for Testing Bipartiteness in General Graphs (2004)
Tali Kaufman, Michael Krivelevich, Dana Ron
In this paper we consider the problem of testing bipartiteness of general graphs. The problem has previously been studied in two models, one most suitable for dense graphs, and one most suitable for...
Alan Frieze, Michael Krivelevich, Oleg Pikhurko, Tibor Szabó
JumbleG is a Maker-Breaker game. Maker and Breaker take turns in choosing edges from the complete graph K n . Maker's aim is to choose what we call an -regular graph (that is, the minimum degree...
Testing Reed Muller Codes \Lambda (2004)
Noga Alon, Tali Kaufman, Michael Krivelevich, Simon Litsyn, Dana Ron
Abstract A code is locally testable if there is a way to indicate with high probability that a vector is far enough from any codeword by accessing only a very small number of the vector's bits....
A Lower Bound on the Density ofSphere Packings via Graph Theory (2004)
Abstract Using graph-theoretic methods we give a new proof that for all sufficiently large n, thereexist sphere packings in Rn of density at least cn2\Gamma n exceeding the classical Minkowskibound...
A lower bound on the density of sphere packings via graph theory (2004)
Krivelevich, Michael, Litsyn, Simon, Vardy, Alexander
Using graph-theoretic methods we give a new proof that for all sufficiently large n, there exist sphere packings in ℝn of density at least cn2−n exceeding the classical Minkowski bound by a...
on distance distributions in codes of given size (2003)
Michael Krivelevich, Simon Litsyn
We prove a new upper bound on the possible distance distribution of a code of a given size. The main instrument of the proof is the Beckner inequality from Harmonic Analysis. We also show that the...
The largest eigenvalue of sparse random graphs (2003)
Michael Krivelevich, Benny Sudakov
We prove that for all values of the edge probability p(n) the largest eigenvalue of a random graph G(n; p) satises almost surely: 1 (G) = (1 + o(1)) maxf p ; npg, where is a maximal degree of G, and...
On packing Hamilton Cycles in ε-Regular Graphs (2003)
Alan Frieze, Michael Krivelevich
A graph G = (V; E) on n vertices is (; )-regular if its minimal degree is at least n, and for every pair of disjoint subsets S; T V of cardinalities at least n, the number of edges e(S; T ) between S...
Addendum to "Scalable Secure Storage when Half the System is (2003)
Faulty Noga Alon, Noga Alon, Haim Kaplan, Michael Krivelevich, Dahlia Malkhi, Julien Stern
Introduction. We consider the following problem. A file of size s bits is to be stored on n disks. Our failure model assumes that a potentially malicious adversary may choose after the file is stored...
The Largest Eigenvalue of Sparse Random Graphs (2003)
Michael Krivelevich, Benny Sudakov
this paper we study eigenvalues of random graphs. The random graph G(n, p)isthe discrete probability space composed of all labelled graphs on the vertices {1,..
The Largest Eigenvalue of Sparse Random Graphs (2003)
Michael Krivelevich, Benny Sudakov
We prove that for all values of the edge probability p(n) the largest eigenvalue of the random graph G(n; p) satis es almost surely: 1 (G) = (1 + o(1)) maxf ; npg, where is the maximum degree of G,...
doi:10.1017/S0963548305007017 Printed in the United Kingdom MaxCut in H-Free Graphs (2003)
Noga Alon, Michael Krivelevich, Benny Sudakov
For a graph G, letf(G) denote the maximum number of edges in a cut of G. For an integer m and for a fixed graph H, letf(m, H) denote the minimum possible cardinality of f(G), as G ranges over all...
The Emergence of a Giant Component in Random Subgraphs of Pseudo-Random Graphs (2003)
Alan Frieze, Michael Krivelevich, Ryan Martin
Let G be a d-regular graph G on n vertices. Suppose that the adjacency matrix of G is such that the eigenvalue which is second largest in absolute value satis es = o(d).
Generalized Hashing and Parent-Identifying Codes (2003)
Noga Alon, Gerard Cohen, Michael Krivelevich, Simon Litsyn
Let C be a code of length n over an alphabet of q letters. For a pair of integers 2 t < u, C is (t; u)-hashing if for any two subsets T ; U C, satisfying T U , jT j = t, jU j = u, there is a...
Tight Bounds for Testing Bipartiteness in General Graphs (2003)
Tali Kaufman, Michael Krivelevich, Dana Ron
In this paper we consider the problem of testing bipartiteness of general graphs. The problem has previously been studied in two models, one most suitable for dense graphs, and one most suitable for...
Induced Subgraphs of Prescribed Size (2003)
Noga Alon Michael, Michael Krivelevich, Benny Sudakov
A subgraph of a graph G is called trivial if it is either a clique or an independent set. Let q(G) denote the maximum number of vertices in a trivial subgraph of G. Motivated by an open problem of...
On packing Hamilton Cycles in ε-regular Graphs (2003)
Alan Frieze, Michael Krivelevich
A graph G = (V; E) on n vertices is (; )-regular if its minimal degree is at least n, and for every pair of disjoint subsets S; T V of cardinalities at least n, the number of edges e(S; T ) between S...
Testing Low-Degree Polynomials over GF(2) (2003)
Noga Alon, Tali Kaufman, Michael Krivelevich, Simon Litsyn, Dana Ron
We describe an efficient randomized algorithm to test if a given binary function f : f0; 1g ! f0; 1g is a low-degree polynomial (that is, a sum of low-degree monomials). For a given integer k 1 and a...
Adding Random Edges to Dense Graphs (2003)
Tom Bohman, Alan Frieze, Michael Krivelevich, Ryan Martin
This paper investigates the addition of random edges to arbitrary dense graphs; in particular, we determine the number of random edges required to ensure various monotone properties including the...
Testing Low-Degree Polynomials over GF(2) (2003)
Noga Alon, Tali Kaufman, Michael Krivelevich, Simon Litsyn, Dana Ron
We describe an efficient randomized algorithm to test if a given binary function f : f0; 1g ! f0; 1g is a low-degree polynomial (that is, a sum of low-degree monomials). For a given integer k 1 and a...
Two-coloring random hypergraphs (2002)
Dimitris Achlioptas, Jeong Han Kim, Michael Krivelevich
A 2-coloring of a hypergraph is a mapping from its vertex set to a set of two colors such that no edge is monochromatic. Let H = H(k;n; p) be a random k-uniform hypergraph on a vertex set V of...
Deciding k-colorability in expected polynomial time (2002)
For every xed k 3 we describe an algorithm for deciding k-colorability, whose expected running time in polynomial in the probability space G(n; p) of random graphs as long as the edge probability p =...
Upper bounds on the rate of LDPC codes (2002)
David Burshtein, Michael Krivelevich, Simon Litsyn, Gadi Miller
We derive upper bounds on the rate of low density parity check (LDPC) codes for which reliable communication is achievable. We rst generalize Gallager's bound to a general binaryinput...
Sparse graphs usually have exponentially many optimal colorings (2002)
A proper coloring of a graph G = (V; E) is called optimal if the number of colors used is the minimal possible one, i.e., it coincides with the chromatic number of G. We investigate a typical...
Sparse Graphs Usually Have Exponentially Many Optimal Colorings (2002)
A proper coloring of a graph G = (V; E) is called optimal if the number of colors used is the minimal possible; i.e., it coincides with the chromatic number of G.
Two-coloring Random Hypergraphs (2002)
Dimitris Achlioptas, Jeong Han Kim, Michael Krivelevich, Prasad Tetali
A 2-coloring of a hypergraph is a mapping from its vertex set to a set of two colors such that no edge is monochromatic. Let H = H(k;n; p) be a random k-uniform hypergraph on a vertex set V of...
Sparse Graphs Usually Have Exponentially Many Optimal Colorings (2002)
A proper coloring of a graph G =(V,E) is called optimal if the number of colors used is the minimal possible; i.e., it coincides with the chromatic number of G.
Coloring Random Graphs - an Algorithmic Perspective (2002)
Algorithmic Graph Coloring and Random Graphs have long become one of the most prominent branches of Combinatorics and Combinatorial Optimization. It is thus very natural to expect that their mixture...
Sparse Pseudo-Random Graphs Are Hamiltonian (2002)
Michael Krivelevich, Benny Sudakov
In this article we study Hamilton cycles in sparse pseudo-random graphs. We prove that if the second largest absolute value λ of an eigenvalue of a d-regular graph G on n vertices...
On the Probability of Independent Sets in Random Graphs (2002)
Michael Krivelevich, Benny Sudakov, Van H. Vu, Vanh. Vu, Nicholas C. Wormald
Let k be the asymptotic value of the independence number of the random graph G(n, p). We prove that if the edge probability p(n) satisfies p(n) ## n n then the probability that G(n, p) does not...
Noga Alon, Michael Krivelevich, Benny Sudakov
For a graph H and an integer n, theTurán number ex(n, H) isthemaximum possible number of edges in a simple graph on n vertices that contains no copy of H. H is rdegenerate if every one of its...
Two-coloring random hypergraphs (2002)
Dimitris Achlioptas, Jeong Han Kim, Michael Krivelevich, Prasad Tetali
ABSTRACT: A 2-coloring of a hypergraph is a mapping from its vertex set to a set of two colors such that no edge is monochromatic. Let H = H�k � n � p � be a random k-uniform hypergraph on a...
THe largest eigenvalue of sparse random graphs (2001)
Krivelevich, Michael, Sudakov, Benny
We prove that for all values of the edge probability p(n) the largest eigenvalue of a random graph G(n,p) satisfies almost surely: \lambda_1(G)=(1+o(1))max{\sqrt{\Delta},np}, where \Delta is a...
Approximating coloring and maximum independent sets in 3-uniform hypergraphs (2001)
Michael Krivelevich, Ram Nathaniel, Benny Sudakov
hypergraphs
Approximating coloring and maximum independent sets in 3-uniform hypergraphs (2001)
Michael Krivelevich, Ram Nathaniel, Benny Sudakov
We discuss approximation algorithms for the coloring problem and the maximum independent set problem in 3-uniform hypergraphs. An algorithm for coloring ˜ 1�5 3-uniform 2-colorable hypergraphs in...
Michael Krivelevich, Benny Sudakov, Tibor Szab Ó
The goal of the paper is to initiate research towards a general, Blow-up Lemma type embedding statement for pseudo-random graphs with sublinear degrees. In particular, we show that if the second...
On the concentration of eigenvalues of random symmetric matrices (2000)
Krivelevich, Michael, Vu, Van H.
We prove that few largest (and most important) eigenvalues of random symmetric matrices of various kinds are very strongly concentrated. This strong concentration enables us to compute the means of...
Scalable Secure Storage when Half the System Is Faulty (2000)
Noga Alon, Haim Kaplan, Michael Krivelevich, Dahlia Malkhi, Julien Stern
In this paper, we provide a method to safely store a document in perhaps the most challenging settings, a highly decentralized replicated storage system where up to half of the storage servers may...
Scalable Secure Storage when Half the System Is Faulty (2000)
Noga Alon, Haim Kaplan, Michael Krivelevich, Dahlia Malkhi, Julien Stern
In this paper, we provide a method to safely store a document in perhaps the most challenging settings, a highly decentralized replicated storage system where up to half of the storage servers may...
On the concentration of eigenvalues of random symmetric matrices (2000)
Noga Alon, Michael Krivelevich, Van H. Vu
It is shown that for every 1 ≤ s ≤ n, the probability that the s-th largest eigenvalue of a random symmetric n-by-n matrix with independent random entries of absolute value at most 1 deviates...
On the concentration of eigenvalues of random symmetric matrices (2000)
Noga Alon, Michael Krivelevich, Van H. Vu
It is shown that for every 1 ≤ s ≤ n, the probability that the s-th largest eigenvalue of a random symmetric n-by-n matrix with independent random entries of absolute value at most 1 deviates...
Scalable Secure Storage when Half the System Is Faulty (2000)
Noga Alon, Haim Kaplan, Michael Krivelevich, Dahlia Malkhi, Julien Stern
In this paper, we provide a method to safely store a document in perhaps the most challenging settings, a highly decentralized replicated storage system where up to half of the storage servers may...
Scalable Secure Storage when Half the System Is Faulty (2000)
Noga Alon, Haim Kaplan, Michael Krivelevich, Dahlia Malkhi, Julien Stern
In this paper, we provide a method to safely store a document in perhaps the most challenging settings, a highly decentralized replicated storage system where up to half of the storage servers may...
On the concentration of eigenvalues of random symmetric matrices (2000)
Noga Alon, Michael Krivelevich, Van H. Vu
It is shown that for every 1 s n, the probability that the s-th largest eigenvalue of a random symmetric n-by-n matrix with independent random entries of absolute value at most 1 deviates from its...
Michael Krivelevich, Benny Sudakov
Given a graph G on n vertices with average degree d, form a random subgraph Gp by choosing each edge of G independently with probability p. Strengthening a classical result of Margulis we prove that,...
Noga Alon, Michael Krivelevich
Let G be a graph on n vertices and suppose that at least n 2 edges have to be deleted from it to make it k-colorable. It is shown that in this case most induced subgraphs of G on ck ln k= 2 vertices...
Regular Languages are Testable with a Constant Number of Queries (1999)
Noga Alon, Michael Krivelevich, Ilan Newman, Mario Szegedy
We continue the study of combinatorial property testing, initiated by Goldreich, Goldwasser and Ron in [7]. The subject of this paper is testing regular languages. Our main result is as follows. For...
Efficient testing of large graphs (1999)
Noga Alon, Eldar Fischer, Michael Krivelevich, Mario Szegedy
Let P be a property of graphs. An -test for P is a randomized algorithm which, given the ability to make queries whether a desired pair of vertices of an input graph G with n vertices are adjacent or...
Noga Alon, Michael Krivelevich
Let G be a graph on n vertices and suppose that at least n 2 edges have to be deleted from it to make it k-colorable. It is shown that in this case most induced subgraphs of G on ck ln k= 2 vertices...
Regular Languages are Testable with a Constant Number of Queries (1999)
Noga Alon, Michael Krivelevich, Ilan Newman, Mario Szegedy
We continue the study of combinatorial property testing, initiated by Goldreich, Goldwasser and Ron in [7]. The subject of this paper is testing regular languages. Our main result is as follows. For...
Regular Languages are Testable with a Constant Number of Queries (1999)
Noga Alon, Michael Krivelevich, Ilan Newman, Mario Szegedy
We continue the study of combinatorial property testing, initiated by Goldreich, Goldwasser and Ron in [7]. The subject of this paper is testing regular languages. Our main result is as follows. For...
Regular Languages are Testable with a Constant Number of Queries (1999)
Noga Alon, Michael Krivelevich, Ilan Newman, Mario Szegedy
We continue the study of combinatorial property testing, initiated by Goldreich, Goldwasser and Ron in [7]. The subject of this paper is testing regular languages. Our main result is as follows. For...
Coloring Graphs with Sparse Neighborhoods (1999)
Noga Alon, Michael Krivelevich, Benny Sudakov
INTRODUCTION The chromatic number /(G) of a graph G is the minimum number of colors required to color all its vertices so that adjacent vertices get distinct colors. It is easy and well known that if...
Efficient testing of large graphs (1999)
Noga Alon, Eldar Fischer, Michael Krivelevich, Mario Szegedy
Let P be a property of graphs. An ɛ-test for P is a randomized algorithm which, given the ability to make queries whether a desired pair of vertices of an input graph G with n vertices are adjacent...
Noga Alon, Michael Krivelevich
Let G be a graph on n vertices and suppose that at least ɛn 2 edges have to be deleted from it to make it k-colorable. It is shown that in this case most induced subgraphs of G on ck ln k/ɛ 2...
Regular Languages are Testable with a Constant Number of Queries (1999)
Noga Alon, Michael Krivelevich, Ilan Newman, Mario Szegedy
We continue the study of combinatorial property testing, initiated by Goldreich, Goldwasser and Ron in [7]. The subject of this paper is testing regular languages. Our main result is as follows. For...
The choice number of random bipartite graphs, lecture at (1998)
Noga Alon, Michael Krivelevich
Abstract. A random bipartite graph G � n � n � p � is obtained by taking two disjoint subsets of vertices A and B of cardinality n each, and by connecting each pair of vertices a � A and b...
Michael Krivelevich, Benny Sudakov
We present a randomized polynomial time algorithm that colors almost every graph on n vertices in n=(log 2 n + c p log 2 n) colors for every positive constant c.
The choice number of random bipartite graphs, lecture at (1998)
Noga Alon, Michael Krivelevich
A random bipartite graph G(n; n; p) is obtained by taking two disjoint subsets of vertices A and B of cardinality n each, and by connecting each pair of vertices a 2 A and b 2 B by an edge randomly...
The Chromatic Numbers of Random Hypergraphs (1998)
Michael Krivelevich, Benny Sudakov
: For a pair of integers 1### r, the #-chromatic number of an r-uniform Z. hypergraph H# V, E is the minimal k, for which there exists a partition of V into subsets ## T,...,T such that e#T ## for...
Approximate Coloring of Uniform Hypergraphs (1998)
Michael Krivelevich Benny, Michael Krivelevich, Benny Sudakov
We consider an algorithmic problem of coloring r-uniform hypergraphs. The problem of finding the exact value of the chromatic number of a hypergraph is known to be NP -hard, so we discuss approximate...
Michael Krivelevich, Benny Sudakov
We present a randomized polynomial time algorithm that colors almost every graph on n vertices in n/(log 2 n + c # log 2 n) colors for every positive constant c. Ó 1998 Published by Elsevier Science...
Finding a Large Hidden Clique in a Random Graph (1998)
Noga Alon, Michael Krivelevich, Benny Sudakov
: We consider the following probabilistic model of a graph on n labeled vertices. Z. First choose a random graph Gn,1#2 , and then choose randomly a subset Q of vertices of size k and force it to be...
Approximate Coloring of Uniform Hypergraphs (1998)
Michael Krivelevich, Benny Sudakov
We consider an algorithmic problem of coloring r-uniform hypergraphs. The problem of finding the exact value of the chromatic number of a hypergraph is known to be NP -hard, so we discuss approximate...
Coloring Graphs With Sparse Neighborhoods (1998)
By Noga Alon, Noga Alon, Michael Krivelevich, Benny Sudakov
It is shown that the chromatic number of any graph with maximum degree d in which the number of edges in the induced subgraph on the set of all neighbors of any vertex does not exceed d 2 =f is at...
Noga Alon, Michael Krivelevich, Benny Sudakov
It is shown that the chromatic number of any graph with maximum degree d in which the number of edges in the induced subgraph on the set of all neighbors of any vertex does not exceed d 2 f is at...
The Chromatic Numbers of Random Hypergraphs (1998)
Michael Krivelevich, Benny Sudakov
For a pair of integers 1 < r, the -chromatic number of an r-uniform hypergraph H = (V; E) is the minimal k, for which there exists a partition of V into subsets T 1 ; : : : ; T k such that je \ T...
The chromatic numbers of random hypergraphs (1998)
Michael Krivelevich, Benny Sudakov
ABSTRACT: For a pair of integers 1���r, the �-chromatic number of an r-uniform hypergraph H � Ž V, E. is the minimal k, for which there exists a partition of V into subsets T,...,T such...
Finding a large hidden clique in a random graph (1998)
Noga Alon, Michael Krivelevich, Benny Sudakov
ABSTRACT: We consider the following probabilistic model of a graph on n labeled vertices. First choose a random graph Gn,1�2 Ž., and then choose randomly a subset Q of vertices of size k and force...
Subgraphs with a large cochromatic number (1997)
Noga Alon, Michael Krivelevich, Benny Sudakov
The cochromatic number of a graph G = (V, E) is the smallest number of parts in a partition of V in which each part is either an independent set or induces a complete subgraph. We show that if the...
The concentration of the chromatic number of random graphs, Combinatorica 17 (1997)
Noga Alon, Michael Krivelevich
We prove that for every constant> 0 the chromatic number of the random graph G(n; p) with p = n
Subgraphs with a large cochromatic number (1997)
Noga Alon, Michael Krivelevich, Benny Sudakov
The cochromatic number of a graph G = (V; E) is the smallest number of parts in a partition of V in which each part is either an independent set or induces a complete subgraph. We show that if the...
Triangle factors in random graphs (1997)
For a graph G = (V; E) on n vertices, where 3 divides n, a triangle factor is a subgraph of G, consisting of n=3 vertex disjoint triangles (complete graphs on three vertices). We discuss the problem...
Constructive bounds for a Ramsey-type problem (1997)
Noga Alon, Michael Krivelevich
For every xed integers r; s satisfying 2 r there exists some = (r; s)> 0 for which we construct explicitly an innite family of graphs H r;s;n, where H r;s;n has n vertices, contains no clique on s...
Subgraphs with a Large Cochromatic Number (1997)
Noga Alon, Michael Krivelevich, Benny Sudakov
: The cochromatic number of a graph G =(V,E) is the smallest number of parts in a partition of V in which each part is either an independent set or induces a complete subgraph. We show that if the...
An Improved Bound on the Minimal Number of Edges in Color-Critical Graphs (1997)
It is proven that for k # 4 and n>kevery k-color-critical graph on n vertices has at least # k-1 2 + k-3 2(k 2 -2k-1) # n edges, thus improving a result of Gallai from 1963. A graph G is...
Constructive bounds for a Ramsey-type problem (1997)
Noga Alon, Michael Krivelevich
For every fixed integers r; s satisfying 2 r ! s there exists some ffl = ffl(r; s) ? 0 for which we construct explicitly an infinite family of graphs H r;s;n , where H r;s;n has n vertices, contains...
The Chromatic Numbers of Random Hypergraphs (1997)
Michael Krivelevich, Beverly Sackler, Faculty Exact Sciences, Benny Sudakov
For a pair of integers 1 fl ! r, the fl-chromatic number of an r-uniform hypergraph H = (V; E) is the minimal k, for which there exists a partition of V into subsets T 1 ; : : : ; T k such that je...
Noga Alon, Michael Krivelevich, Benny Sudakov
The choice number of a graph G is the minimum integer k such that for every assignment of asetS(v) ofkcolors to every vertex v of G, there is a proper coloring of G that assigns to each vertex v a...
Subgraphs with a large cochromatic number (1997)
Noga Alon, Michael Krivelevich, Benny Sudakov
Abstract: The cochromatic number of a graph G =(V,E) is the smallest number of parts in a partition of V in which each part is either an independent set or induces a complete subgraph. We show that...
On k-saturated graphs with restrictions on the degrees (1996)
Noga Alon, Paul Erdős, Ron Holzman, Michael Krivelevich
A graph G is called k-saturated, where k ≥ 3 is an integer, if G is K k-free but the addition of any edge produces a K k (we denote by K k a complete graph on k vertices). We investigate...
On a theorem of Lovasz on covers in r-partite hypergraphs (1996)
Ron Aharoni, Ron Holzman, Michael Krivelevich
(H) r=2 for every r-partite hypergraph H (where and denote the covering number and fractional covering number respectively). Here it is shown that the same upper bound is valid for a more general...
Perfect fractional matchings in random hypergraphs, Random Structures and Algorithms 9 (1996)
Given an r-uniform hypergraph H = (V; E) on jV j = n vertices, a real-valued function f: E! R is called a perfect fractional matching if P v2e f(e) 1 for all v 2 V and
Triangle Factors in Random Graphs (1996)
Michael Krivelevich, Raymond And Beverly Sackler
For a graph G = (V; E) on n vertices, where 3 divides n, a triangle factor is a subgraph of G, consisting of n=3 vertex disjoint triangles (complete graphs on three vertices). We discuss the problem...
On the edge distribution in triangle-free graphs (1995)
Abstract. Two problems on the edge distribution in triangle-free graphs are considered: 1) Given an 0 1. Find the largest = () such that for innitely many n there exists a triangle-free graph G on n...
Random regular graphs of high degree (1982)
Michael Krivelevich, Benny Sudakov, Van H. Vu, Nicholas C. Wormald
ABSTRACT: Random d-regular graphs have been well studied when d is fixed and the number of vertices goes to infinity. We obtain results on many of the properties of a random d-regular graph when d =...
Efficient Testing of Large Graphs
Noga Alon, Eldar Fischer, Michael Krivelevich, Mario Szegedy
Let P be a property of graphs. An ffl-test for P is a randomized algorithm which, given the ability to make queries whether a desired pair of vertices of an input graph G with n vertices are adjacent...
An Improved Bound on the Minimal Number of Edges in Color-Critical Graphs
Michael Krivelevich School, Michael Krivelevich
It is proven that for k # 4 and n > k every k-color-critical graph on n vertices has at least # k-1 2 + k-3 2(k 2 -2k-1) # n edges, thus improving a result of Gallai from 1963. A graph G is...
List Coloring of Random and Pseudo-Random Graphs
Noga Alon, Michael Krivelevich, Benny Sudakov
The choice number of a graph G is the minimum integer k such that for every assignment of a set S(v) of k colors to every vertex v of G, there is a proper coloring of G that assigns to each vertex v...
Random Regular Graphs of High Degree
Michael Krivelevich, Benny Sudakov, Van H. Vu, Nicholas C. Wormald
Random d-regular graphs have been well studied when d is fixed and the number of vertices goes to infinity. We obtain results on many of the properties of a random d-regular graphs when d = d(n)...
Coloring Graphs with Sparse Neighborhoods
Noga Alon, Michael Krivelevich, Benny Sudakov
It is shown that the chromatic number of any graph with maximum degree d in which the number of edges in the induced subgraph on the set of all neighbors of any vertex does not exceed d 2 =f is at...
Michael Krivelevich, Benny Sudakov
this paper and to make it more coherent, usually the parameters are denoted (v; k; ; )). Two simple examples of strongly regular graph are the pentagon C 5 that has parameters (5; 2; 0; 1), and the...
The Choice Number of Dense Random Graphs
We prove that if the edge probability p(n) satis es n p(n) 3=4, where 0 < < 1=4 is a constant, then the choice number and the chromatic number of the random graph G(n; p) are almost surely...
Maximum Cuts and Judicious Partitions in Graphs without Short Cycles
Noga Alon, Bela Bollobas, Michael Krivelevich, Benny Sudakov
We consider the bipartite cut and the judicious partition problems in graphs of girth at least 4. For the bipartite cut problem we show that every graph G with m edges, whose shortest cycle has...
List Coloring of Random and Pseudo-Random Graphs
Noga Alon, Michael Krivelevich, Benny Sudakov
The choice number of a graph G is the minimum integer k such that for every assignment of a set S(v) of k colors to every vertex v of G, there is a proper coloring of G that assigns to each vertex v...