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Related papers: The Lovasz number of random graphs

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Answering a question of Gamarnik and Smedira, we give a polynomial time algorithm that approximately computes the volume of a truncation of a relaxation of the independent set polytope, improving on their quasi-polynomial time algorithm.…

Combinatorics · Mathematics 2024-04-15 Ferenc Bencs , Guus Regts

The chromatic number of a very dense random graph $G(n,p)$, with $p \ge 1 - n^{-c}$ for some constant $c > 0$, was first studied by Surya and Warnke, who conjectured that the typical deviation of $\chi(G(n,p))$ from its mean is of order…

Combinatorics · Mathematics 2024-05-27 Zhifei Yan

In this paper, we study cliques and chromatic number of inhomogenous random graphs where the individual edge probabilities could be arbitrarily low. We use a recursive method to obtain estimates on the maximum clique size under a mild…

Probability · Mathematics 2017-04-18 Ghurumuruhan Ganesan

We prove the following local strengthening of Shearer's classic bound on the independence number of triangle-free graphs: For every triangle-free graph $G$ there exists a probability distribution on its independent sets such that every…

Combinatorics · Mathematics 2025-01-03 Anders Martinsson , Raphael Steiner

The problem of uniformly sampling hypergraph independent sets is revisited. We design an efficient perfect sampler for the problem under a condition similar to that of the asymmetric Lov\'asz Local Lemma. When applied to $d$-regular…

Data Structures and Algorithms · Computer Science 2022-09-14 Guoliang Qiu , Yanheng Wang , Chihao Zhang

We prove a formula for the asymptotic number of edge-colored regular graphs with a prescribed set of allowed vertex-incidence structures. The formula depends on specific critical points of a polynomial encoding the vertex-incidences. As an…

Combinatorics · Mathematics 2026-01-28 Michael Borinsky , Chiara Meroni , Maximilian Wiesmann

By implementing algorithmic versions of Sapozhenko's graph container methods, we give new algorithms for approximating the number of independent sets in bipartite graphs. Our first algorithm applies to $d$-regular, bipartite graphs…

Data Structures and Algorithms · Computer Science 2021-09-09 Matthew Jenssen , Will Perkins , Aditya Potukuchi

We prove that a large family of pairs of graphs satisfy a polynomial dependence in asymmetric graph removal lemmas. In particular, we give an unexpected answer to a question of Gishboliner, Shapira, and Wigderson by showing that for every…

Combinatorics · Mathematics 2023-10-30 António Girão , Eoin Hurley , Freddie Illingworth , Lukas Michel

The Lov\'asz Local Lemma is a classic result in probability theory that is often used to prove the existence of combinatorial objects via the probabilistic method. In its simplest form, it states that if we have $n$ `bad events', each of…

Distributed, Parallel, and Cluster Computing · Computer Science 2022-10-20 Peter Davies

The linear complementarity problem is a continuous optimization problem that generalizes convex quadratic programming, Nash equilibria of bimatrix games and several such problems. This paper presents a continuous optimization formulation…

Discrete Mathematics · Computer Science 2018-10-19 Parthe Pandit , Ankur A. Kulkarni

The celebrated Erdos, Faber and Lovasz conjecture may be stated as follows: Any linear hypergraph on v points has chromatic index at most v. We will introduce the linear intersection number of a graph, and use this number to give an…

Combinatorics · Mathematics 2007-05-23 Hauke Klein , Marian Margraf

The following relaxation of proper coloring the square of a graph was recently introduced: for a positive integer $h$, the proper $h$-conflict-free chromatic number of a graph $G$, denoted $\chi_{pcf}^h(G)$, is the minimum $k$ such that $G$…

Combinatorics · Mathematics 2024-04-18 Eun-Kyung Cho , Ilkyoo Choi , Hyemin Kwon , Boram Park

Let $\Gamma$ be the graph whose vertices are the chambers of the finite projective space $PG(3,q)$ with two vertices being adjacent when the corresponding chambers are in general position. It is known that the independence number of this…

Combinatorics · Mathematics 2021-02-15 Klaus Metsch

A Kneser graph $KG_{n,k}$ is a graph whose vertices are in one-to-one correspondence with $k$-element subsets of $[n],$ with two vertices connected if and only if the corresponding sets do not intersect. A famous result due to Lov\'asz…

Combinatorics · Mathematics 2017-12-01 Andrey Borisovich Kupavskii

In this paper, we develop efficient exact and approximate algorithms for computing a maximum independent set in random graphs. In a random graph $G$, each pair of vertices are joined by an edge with a probability $p$, where $p$ is a…

Data Structures and Algorithms · Computer Science 2013-08-08 Yinglei Song

In the way of proving Kneser's conjecture, L\'{a}szl\'{o} Lov\'{a}sz settled out a new lower bound for the chromatic number of graphs. He showed that if the hom complex $||Hom(\mathcal{K}_2, H)||$ of a graph $H$ is topologically…

Combinatorics · Mathematics 2017-09-21 Hamid Reza Daneshpajouh

Motivated by algorithmic applications, Kun, O'Brien, Pilipczuk, and Sullivan introduced the parameter linear chromatic number as a relaxation of treedepth and proved that the two parameters are polynomially related. They conjectured that…

Combinatorics · Mathematics 2026-03-12 Claire Hilaire , Matjaž Krnc , Martin Milanič , Jean-Florent Raymond

Let G be a graph. The independence-domination number is the maximum over all independent sets I in G of the minimal number of vertices needed to dominate I. In this paper we investigate the computational complexity of independence…

Discrete Mathematics · Computer Science 2013-04-25 Wing-Kai Hon , Ton Kloks , Hsiang Hsuan Liu , Sheung-Hung Poon , Yue-Li Wang

The dichromatic number of a digraph $D$ is the smallest $k$ such that $D$ can be partitioned into $k$ acyclic subdigraphs, and the dichromatic number of an undirected graph is the maximum dichromatic number over all its orientations.…

Combinatorics · Mathematics 2025-04-22 Ararat Harutyunyan , Gil Puig i Surroca

In this note, we investigate some properties of local Kneser graphs defined in [8]. In this regard, as a generalization of the Erd${\rm \ddot{o}}$s-Ko-Rado theorem, we characterize the maximum independent sets of local Kneser graphs. Next,…

Combinatorics · Mathematics 2009-02-24 Meysam Alishahi , Hossein Hajiabolhassan , Ali Taherkhani