English
Related papers

Related papers: On the chromatic number of random regular graphs

200 papers

The clique chromatic number of a graph G=(V,E) is the minimum number of colors in a vertex coloring so that no maximal (with respect to containment) clique is monochromatic. We prove that the clique chromatic number of the binomial random…

Combinatorics · Mathematics 2017-11-07 Noga Alon , Michael Krivelevich

Let $G$ be a $d$-regular graph on $n$ vertices. Frieze, Gould, Karo\'nski and Pfender began the study of the following random spanning subgraph model $H=H(G)$. Assign independently to each vertex $v$ of $G$ a uniform random number $x(v) \in…

Combinatorics · Mathematics 2022-07-28 Jacob Fox , Sammy Luo , Huy Tuan Pham

For $k\ge 1$, we consider interleaved $k$-tuple colorings of the nodes of a graph, that is, assignments of $k$ distinct natural numbers to each node in such a way that nodes that are connected by an edge receive numbers that are strictly…

Combinatorics · Mathematics 2013-02-13 V. C. Barbosa

A colouring of a graph $G=(V,E)$ is a function $c: V\rightarrow\{1,2,\ldots \}$ such that $c(u)\neq c(v)$ for every $uv\in E$. A $k$-regular list assignment of $G$ is a function $L$ with domain $V$ such that for every $u\in V$, $L(u)$ is a…

Data Structures and Algorithms · Computer Science 2019-02-08 Konrad K. Dabrowski , Francois Dross , Matthew Johnson , Daniel Paulusma

We study the maximization version of the fundamental graph coloring problem. Here the goal is to color the vertices of a k-colorable graph with k colors so that a maximum fraction of edges are properly colored (i.e. their endpoints receive…

Computational Complexity · Computer Science 2015-05-14 Venkatesan Guruswami , Ali Kemal Sinop

Let $H=(V(H),E(H))$ be a graph. A $k$-coloring of $H$ is a mapping $\pi : V(H) \longrightarrow \{1,2,\ldots, k\}$, if each color class induces a $K_2$-free subgraph. For a graph $G$ of order at least $2$, a $G$-free $k$-coloring of $H$, is…

Combinatorics · Mathematics 2022-01-13 Yaser Rowshan

A coloring is distinguishing (or symmetry breaking) if no non-identity automorphism preserves it. The distinguishing threshold of a graph $G$, denoted by $\theta(G)$, is the minimum number of colors $k$ so that every $k$-coloring of $G$ is…

Combinatorics · Mathematics 2022-12-19 Saeid Alikhani , Mohammad Hadi Shekarriz

Given positive integers $n\ge 2k$, the {\it Kneser graph} $KG_{n,k}$ is a graph whose vertex set is the collection of all $k$-element subsets of the set $\{1,\ldots, n\}$, with edges connecting pairs of disjoint sets. One of the classical…

Combinatorics · Mathematics 2021-07-20 Sergei Kiselev , Andrey Kupavskii

DP-coloring (also called correspondence coloring) of graphs is a generalization of list coloring that has been widely studied since its introduction by Dvo\v{r}\'{a}k and Postle in $2015$. Intuitively, DP-coloring generalizes list coloring…

Combinatorics · Mathematics 2025-02-11 Anton Bernshteyn , Daniel Dominik , Hemanshu Kaul , Jeffrey A. Mudrock

The classical theorem of Vizing states that every graph of maximum degree $d$ admits an edge-coloring with at most $d+1$ colors. Furthermore, as it was earlier shown by K\H{o}nig, $d$ colors suffice if the graph is bipartite. We investigate…

Combinatorics · Mathematics 2016-08-23 Endre Csóka , Gabor Lippner , Oleg Pikhurko

In the first part of this paper, we consider weighted domination in the case where the vertices of the complete graph on~\(n\) vertices are equipped with independent and identically distributed (i.i.d.) weights. We use the probabilistic…

Probability · Mathematics 2023-01-16 Ghurumuruhan Ganesan

We prove that whenever $d=d(n)\to\infty$ and $n-d\to\infty$ as $n\to\infty$, then with high probability for any non-trivial initial colouring, the colour refinement algorithm distinguishes all vertices of the random regular graph…

Combinatorics · Mathematics 2026-02-20 Mikhail Isaev , Tamás Makai , Brendan McKay , Pawel Pralat , Jane Tan , Maksim Zhukovskii

Given a graph $G$ and a positive integer $d$, an orthogonal vector $d$-coloring of $G$ is an assignment $f$ of vectors of $\mathbb{R}^d$ to $V(G)$ in such a way that adjacent vertices receive orthogonal vectors. The orthogonal chromatic…

Discrete Mathematics · Computer Science 2019-09-05 Ana Silva , Allen Ibiapina

We extend Bollobas' classical result on the chromatic number of a binomial random graph to the exchangeable random graph model $\mathcal{G}(n,W)$ defined by a graphon $W:[0,1]^2 \rightarrow [0,1]$, which is a symmetric measurable function.…

Combinatorics · Mathematics 2023-05-15 Mikhail Isaev , Mihyun Kang

An edge-colouring of a graph is distinguishing, if the only automorphism which preserves the colouring is the identity. It has been conjectured that all but finitely many connected, finite, regular graphs admit a distinguishing…

Combinatorics · Mathematics 2020-05-11 Florian Lehner , Monika Pilśniak , Marcin Stawiski

The genus of a graph is a topological invariant that measures the minimum genus of a surface on which the graph can be embedded without any edges crossing. Graph genus plays a fundamental role in topological graph theory, used to classify…

Combinatorics · Mathematics 2023-01-31 Lucas Blakeslee

The clique chromatic number of a graph is the smallest number of colors in a vertex coloring so that no maximal clique is monochromatic. In this paper, we determine the order of magnitude of the clique chromatic number of the random graph…

Combinatorics · Mathematics 2025-06-04 Manuel Fernandez , Lutz Warnke

Let $\mathcal{C}_k(n)$ be the family of all connected $k$-chromatic graphs of order $n$. Given a natural number $x\geq k$, we consider the problem of finding the maximum number of $x$-colorings among graphs in $\mathcal{C}_k(n)$. When…

Combinatorics · Mathematics 2018-05-25 Aysel Erey

A vertex coloring of a given simple graph $G=(V,E)$ with $k$ colors ($k$-coloring) is a map from its vertex set to the set of integers $\{1,2,3,\dots, k\}$. A coloring is called perfect if the multiset of colors appearing on the neighbours…

Combinatorics · Mathematics 2020-05-29 O. G. Parshina , M. A. Lisitsyna

DP-coloring is a generalization of list coloring introduced recently by Dvo\v{r}\'ak and Postle. We prove that for every $n$-vertex graph $G$ whose chromatic number $\chi(G)$ is "close" to $n$, the DP-chromatic number of $G$ equals…

Combinatorics · Mathematics 2018-03-26 Anton Bernshteyn , Alexandr Kostochka , Xuding Zhu