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Related papers: Random cliques in random graphs revisited

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We present fast and efficient randomized distributed algorithms to find Hamiltonian cycles in random graphs. In particular, we present a randomized distributed algorithm for the $G(n,p)$ random graph model, with number of nodes $n$ and…

Data Structures and Algorithms · Computer Science 2018-04-25 Soumyottam Chatterjee , Reza Fathi , Gopal Pandurangan , Nguyen Dinh Pham

Let k_r(n,m) denote the minimum number of r-cliques in graphs with n vertices and m edges. For r=3,4 we give a lower bound on k_r(n,m) that approximates k_r(n,m) with an error smaller than n^r/(n^2-2m). The solution is based on a constraint…

Combinatorics · Mathematics 2008-02-19 Vladimir Nikiforov

We prove that for each integer $r\geq 2$, there exists a constant $C_r>0$ with the following property: for any $0<\varepsilon \leq 1/2$ and any graph $G$ with clique number at most $r,$ there is a partition of $V(G)$ into at most…

Combinatorics · Mathematics 2024-12-02 António Girão , Toby Insley

We find the threshold for the existence of a collection of edge disjoint copies of $K_r$ that form a cyclic structure and span all vertices of $G_{n,p}$. We use a recent result of Riordan to give a two line proof of the main result.

Combinatorics · Mathematics 2020-06-01 Alan Frieze

We establish a novel connection between the well-known chromatic threshold problem in extremal combinatorics and the celebrated $(p,q)$-theorem in discrete geometry. In particular, for a graph $G$ with bounded clique number and a natural…

Combinatorics · Mathematics 2024-08-28 Hong Liu , Chong Shangguan , Jozef Skokan , Zixiang Xu

Let $\mathcal{H}$ be a family of graphs. The generalized Tur\'an number $ex(n, K_r, \mathcal{H})$ is the maximum number of copies of the clique $K_r$ in any $n$-vertex $\mathcal{H}$-free graph. In this paper, we determine the value of…

Combinatorics · Mathematics 2024-09-17 Xiaona Fang , Xiutao Zhu , Yaojun Chen

Many NP-complete graph problems are polynomial-time solvable on graph classes of bounded clique-width. Several of these problems are polynomial-time solvable on a hereditary graph class ${\cal G}$ if they are so on the atoms (graphs with no…

Discrete Mathematics · Computer Science 2026-02-19 Konrad K. Dabrowski , Tomáš Masařík , Jana Novotná , Daniël Paulusma , Paweł Rzążewski

We consider the problem of finding a large clique in an Erd\H{o}s--R\'enyi random graph where we are allowed unbounded computational time but can only query a limited number of edges. Recall that the largest clique in $G \sim G(n,1/2)$ has…

Combinatorics · Mathematics 2024-07-12 Endre Csóka , András Pongrácz

We study the algorithmic decidability of the domination number in the Erdos-Renyi random graph model $G(n,p)$. We show that for a carefully chosen edge probability $p=p(n)$, the domination problem exhibits a strong irreducible property.…

Computational Complexity · Computer Science 2026-04-28 Guangyan Zhou

For two graphs $G$ and $H$, write $G \stackrel{\mathrm{rbw}}{\longrightarrow} H$ if $G$ has the property that every \emph{proper} colouring of its edges yields a \emph{rainbow} copy of $H$. We study the thresholds for such so-called…

Combinatorics · Mathematics 2022-07-18 Elad Aigner-Horev , Oran Danon , Dan Hefetz , Shoham Letzter

We study the following generalization of the Tur\'an problem in sparse random graphs. Given graphs $T$ and $H$, let $\mathrm{ex}\big(G(n,p), T, H\big)$ be the random variable that counts the largest number of copies of $T$ in a subgraph of…

Combinatorics · Mathematics 2019-03-20 Wojciech Samotij , Clara Shikhelman

For fixed graphs $F$ and $H$, the generalized Tur\'an problem asks for the maximum number $ex(n,H,F)$ of copies of $H$ that an $n$-vertex $F$-free graph can have. In this paper, we focus on cases with $F$ being $B_{r,s}$, the graph…

Combinatorics · Mathematics 2022-02-08 Dániel Gerbner , Balázs Patkós

Let ccl(G) denote the order of the largest complete minor in a graph G (also called the contraction clique number) and let G(n,p) denote a random graph on n vertices with edge probability p. Bollobas, Catlin and Erdos asymptotically…

Combinatorics · Mathematics 2007-05-23 N. Fountoulakis , D. Kühn , D. Osthus

Given a graph $G$ and $p\in [0,1]$, the random subgraph $G_p$ is obtained by retaining each edge of $G$ independently with probability $p$. We show that for every $\epsilon>0$, there exists a constant $C>0$ such that the following holds.…

Combinatorics · Mathematics 2024-07-24 Sahar Diskin , Joshua Erde , Mihyun Kang , Michael Krivelevich

A circulant graph H is defined on the set of vertices V=\left\{ 1,\ldots,n\right\} and edges E=\left\{ \left(i,j\right):\left|i-j\right|\equiv s\left(\textrm{mod}n\right),s\in S\right\} , where S\subseteq\left\{…

Combinatorics · Mathematics 2017-07-17 Sebastian Richter , Israel Rocha

Discovering the underlying structures present in large real world graphs is a fundamental scientific problem. In this paper we show that a graph's clique tree can be used to extract a hyperedge replacement grammar. If we store an ordering…

Social and Information Networks · Computer Science 2016-08-11 Salvador Aguiñaga , Rodrigo Palacios , David Chiang , Tim Weninger

Two central topics of study in combinatorics are the so-called evolution of random graphs, introduced by the seminal work of Erd\H{o}s and R\'enyi, and the family of $H$-free graphs, that is, graphs which do not contain a subgraph…

Combinatorics · Mathematics 2017-12-12 József Balogh , Robert Morris , Wojciech Samotij , Lutz Warnke

In this paper we study the threshold model of \emph{geometric inhomogeneous random graphs} (GIRGs); a generative random graph model that is closely related to \emph{hyperbolic random graphs} (HRGs). These models have been observed to…

Discrete Mathematics · Computer Science 2023-06-19 Thomas Bläsius , Tobias Friedrich , Maximilian Katzmann , Janosch Ruff , Ziena Zeif

We count orientations of $G(n,p)$ avoiding certain classes of oriented graphs. In particular, we study $T_r(n,p)$, the number of orientations of the binomial random graph $G(n,p)$ in which every copy of $K_r$ is transitive, and $S_r(n,p)$,…

Combinatorics · Mathematics 2020-01-01 Maurício Collares , Yoshiharu Kohayakawa , Robert Morris , Guilherme Oliveira Mota

Given an $n$-vertex pseudorandom graph $G$ and an $n$-vertex graph $H$ with maximum degree at most two, we wish to find a copy of $H$ in $G$, i.e.\ an embedding $\varphi\colon V(H)\to V(G)$ so that $\varphi(u)\varphi(v)\in E(G)$ for all…

Combinatorics · Mathematics 2023-04-06 Jie Han , Yoshiharu Kohayakawa , Patrick Morris , Yury Person