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Related papers: A Coloring Algorithm for $4K_1$-free line graphs

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We consider the flexible list coloring problem, in which we have a graph $G$, a color list assignment $L:V(G) \rightarrow 2^{\mathbb N}$, and a set $U \subseteq V(G)$ of vertices such that each $u \in U$ has a preferred color $p(u) \in…

Combinatorics · Mathematics 2024-08-19 Richard Bi , Peter Bradshaw

For any finite set $\mathcal{H} = \{H_1,\ldots,H_p\}$ of graphs, a graph is $\mathcal{H}$-subgraph-free if it does not contain any of $H_1,\ldots,H_p$ as a subgraph. In recent work, meta-classifications have been studied: these show that if…

Data Structures and Algorithms · Computer Science 2023-05-03 Matthew Johnson , Barnaby Martin , Sukanya Pandey , Daniël Paulusma , Siani Smith , Erik Jan van Leeuwen

A conflict-free $k$-coloring of a graph $G=(V,E)$ assigns one of $k$ different colors to some of the vertices such that, for every vertex $v$, there is a color that is assigned to exactly one vertex among $v$ and $v$'s neighbors. Such…

Computational Geometry · Computer Science 2017-09-13 Sándor P. Fekete , Phillip Keldenich

For a positive integer $r$ and graphs $G$ and $H$, we denote by $G+H$ the disjoint union of $G$ and $H$, and by $rH$ the union of $r$ mutually disjoint copies of $H$. Also, we say $G$ is $H$-free if $H$ is not isomorphic to an induced…

Combinatorics · Mathematics 2023-09-06 Sepehr Hajebi , Yanjia Li , Sophie Spirkl

A graph coloring has bounded clustering if each monochromatic component has bounded size. This paper studies such a coloring, where the number of colors depends on an excluded complete bipartite subgraph. This is a much weaker assumption…

Combinatorics · Mathematics 2022-09-29 Chun-Hung Liu , David R. Wood

We show that for any nonnegative integer $r$, the Weighted Maximum List-$k$-Colourable Induced Subgraph problem can be solved in polynomial time for input graphs that do not contain $(P_5+ rK_1)$ as an induced subgraph, and give an explicit…

Combinatorics · Mathematics 2025-11-17 Cicely Henderson , Evelyne Smith-Roberge , Sophie Spirkl , Rebecca Whitman

It is known that, for any $k$-list assignment $L$ of a graph $G$, the number of $L$-list colorings of $G$ is at least the number of the proper $k$-colorings of $G$ when $k>(m-1)/\ln(1+\sqrt{2})$. In this paper, we extend the Whitney's…

Combinatorics · Mathematics 2022-07-13 Sumin Huang , Jianguo Qian , Wei Wang

A \emph{hole} is a chordless cycle of length at least $4$. A graph is \emph{even-hole-free} if it does not contain any hole of even length as an induced subgraph. In this paper, we study the class of even-hole-free graphs with no star…

Discrete Mathematics · Computer Science 2018-06-08 Ngoc Khang Le

We give the first polynomial-time algorithm for coloring vertices of P_5-free graphs with k colors. This settles an open problem and generalizes several previously known results.

Discrete Mathematics · Computer Science 2007-05-23 Marcin Kaminski , Vadim Lozin

We consider the problem of clique coloring, that is, coloring the vertices of a given graph such that no (maximal) clique of size at least two is monocolored. It is known that interval graphs are $2$-clique colorable. In this paper we prove…

Combinatorics · Mathematics 2023-04-04 Flavia Bonomo , María Pía Mazzoleni , Maya Stein

A graph $G$ is $k$-vertex-critical if $G$ has chromatic number $k$ but every proper induced subgraph of $G$ has chromatic number less than $k$. The study of $k$-vertex-critical graphs for graph classes is an important topic in algorithmic…

Combinatorics · Mathematics 2021-08-21 Qingqiong Cai , Jan Goedgebeur , Shenwei Huang

A conflict-free coloring of a graph $G$ is a (partial) coloring of its vertices such that every vertex $u$ has a neighbor whose assigned color is unique in the neighborhood of $u$. There are two variants of this coloring, one defined using…

Discrete Mathematics · Computer Science 2024-03-12 Sriram Bhyravarapu , Tim A. Hartmann , Hung P. Hoang , Subrahmanyam Kalyanasundaram , I. Vinod Reddy

We study the Max Partial $k$-Coloring problem, where we are given a vertex-weighted graph, and we ask for a maximum-weight induced subgraph that admits a proper $k$-coloring. For $k=1$ this problem coincides with Maximum Weight Independent…

Computational Complexity · Computer Science 2025-04-15 Nadzieja Hodur , Monika Pilśniak , Magdalena Prorok , Paweł Rzążewski

For given graph $H$ and graphical property $P$, the conditional chromatic number $\chi(H,P)$ of $H$, is the smallest number $k$, so that $V(H)$ can be decomposed into sets $V_1,V_2,\ldots, V_k$, in which $H[V_i]$ satisfies the property $P$,…

Combinatorics · Mathematics 2022-01-19 Yaser Rowshan

In this paper, we consider distributed coloring for planar graphs with a small number of colors. We present an optimal (up to a constant factor) $O(\log{n})$ time algorithm for 6-coloring planar graphs. Our algorithm is based on a novel…

Data Structures and Algorithms · Computer Science 2018-04-03 Shiri Chechik , Doron Mukhtar

We define a perfect coloring of a graph $G$ as a proper coloring of $G$ such that every connected induced subgraph $H$ of $G$ uses exactly $\omega(H)$ many colors where $\omega(H)$ is the clique number of $H$. A graph is perfectly colorable…

Combinatorics · Mathematics 2011-08-15 R B Sandeep

In the problem of 2-coloring without monochromatic triangles (or triangle-tree 2-coloring), vertices of the simple, connected, undirected graph are colored with either 'black' or 'white' such that there are no 3 mutually adjacent vertices…

Data Structures and Algorithms · Computer Science 2021-10-12 Michał Karpiński , Krzysztof Piecuch

In this paper, we give a polynomial time algorithm which determines if a given triangle-free graph with no induced seven-vertex path is 3-colorable, and gives an explicit coloring if one exists.

Combinatorics · Mathematics 2014-09-19 Maria Chudnovsky , Peter Maceli , Mingxian Zhong

Given two graphs $H_1$ and $H_2$, a graph $G$ is $(H_1,H_2)$-free if it contains no subgraph isomorphic to $H_1$ or $H_2$. We continue a recent study into the clique-width of $(H_1,H_2)$-free graphs and present three new classes of…

Discrete Mathematics · Computer Science 2015-01-14 Konrad K. Dabrowski , Shenwei Huang , Daniël Paulusma

Proper graph coloring assigns different colors to adjacent vertices of the graph. Usually, the number of colors is fixed or as small as possible. Consider applications (e.g. variants of scheduling) where colors represent limited resources…

Combinatorics · Mathematics 2019-09-10 Tomáš Masařík
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