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Related papers: Improved bounds for weak coloring numbers

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Motivated by the study of greedy algorithms for graph coloring, Bernshteyn and Lee introduced a generalization of graph degeneracy, which is called weak degeneracy. In this paper, we show the lower bound of the weak degeneracy for…

Combinatorics · Mathematics 2023-10-02 Yuxuan Yang

We study the growth rate of weak coloring numbers of graphs excluding a fixed graph as a minor. Van den Heuvel et al. (European J. of Combinatorics, 2017) showed that for a fixed graph $X$, the maximum $r$-th weak coloring number of…

Combinatorics · Mathematics 2025-04-07 Jędrzej Hodor , Hoang La , Piotr Micek , Clément Rambaud

Motivated by the study of greedy algorithms for graph coloring, we introduce a new graph parameter, which we call weak degeneracy. By definition, every $d$-degenerate graph is also weakly $d$-degenerate. On the other hand, if $G$ is weakly…

Combinatorics · Mathematics 2022-11-28 Anton Bernshteyn , Eugene Lee

Weak and strong coloring numbers are generalizations of the degeneracy of a graph, where for each natural number $k$, we seek a vertex ordering such every vertex can (weakly respectively strongly) reach in $k$ steps only few vertices with…

Combinatorics · Mathematics 2021-04-08 Zdeněk Dvořák , Jakub Pekárek , Torsten Ueckerdt , Yelena Yuditsky

The weak degeneracy of a graph $G$ is a numerical parameter that was recently introduced by the first two authors with the aim of understanding the power of greedy algorithms for graph coloring. Every $d$-degenerate graph is weakly…

Combinatorics · Mathematics 2025-06-06 Anton Bernshteyn , Eugene Lee , Evelyne Smith-Roberge

The weak $r$-coloring numbers $wcol_r(G)$ of a graph $G$ were introduced by the first two authors as a generalization of the usual coloring number $col(G)$, and have since found interesting theoretical and algorithmic applications. This has…

Combinatorics · Mathematics 2020-02-11 H. A. Kierstead , Daqing Yang , Junjun Yi

The generalised colouring numbers $\mathrm{col}_r(G)$ and $\mathrm{wcol}_r(G)$ were introduced by Kierstead and Yang as a generalisation of the usual colouring number, and have since then found important theoretical and algorithmic…

Bounded expansion and nowhere-dense classes of graphs capture the theoretical tractability for several important algorithmic problems. These classes of graphs can be characterized by the so-called weak coloring numbers of graphs, which…

Data Structures and Algorithms · Computer Science 2022-09-27 Alexander Dobler , Manuel Sorge , Anaïs Villedieu

A graph is $k$-degenerate if every subgraph $H$ has a vertex $v$ with $d_{H}(v) \leq k$. The class of degenerate graphs plays an important role in the graph coloring theory. Observed that every $k$-degenerate graph is $(k + 1)$-choosable…

Combinatorics · Mathematics 2023-03-24 Tao Wang

Bernshteyn and Lee defined a new notion, weak degeneracy, which is slightly weaker than the ordinary degeneracy. It is proved that strictly $f$-degenerate transversal is a common generalization of list coloring, $L$-forested-coloring and…

Combinatorics · Mathematics 2022-07-05 Qianqian Wang , Tao Wang , Xiaojing Yang

The \textit{$k$-weak-dynamic number} of a graph $G$ is the smallest number of colors we need to color the vertices of $G$ in such a way that each vertex $v$ of degree $d(v)$ sees at least $\rm{min}\{k,d(v)\}$ colors on its neighborhood. We…

Combinatorics · Mathematics 2018-02-19 Caroline Accurso , Vitaliy Chernyshov , Leaha Hand , Sogol Jahanbekam , Paul Wenger

It was shown by Grohe et al. that nowhere dense classes of graphs admit sparse neighbourhood covers of small degree. We show that a monotone graph class admits sparse neighbourhood covers if and only if it is nowhere dense. The existence of…

The generalized coloring numbers of Kierstead and Yang (Order 2003) offer an algorithmically-useful characterization of graph classes with bounded expansion. In this work, we consider the hardness and approximability of these parameters.…

Computational Complexity · Computer Science 2023-03-17 Michael Breen-McKay , Brian Lavallee , Blair D. Sullivan

We resolve a number of long-standing open problems in online graph coloring. More specifically, we develop tight lower bounds on the performance of online algorithms for fundamental graph classes. An important contribution is that our…

Data Structures and Algorithms · Computer Science 2017-07-04 Susanne Albers , Sebastian Schraink

Thomassen showed that planar graphs are 5-list-colourable, and that planar graphs of girth at least five are 3-list-colourable. An easy degeneracy argument shows that planar graphs of girth at least four are 4-list-colourable. In 2022,…

Combinatorics · Mathematics 2025-05-01 Ewan Davies , Evelyne Smith-Roberge

A graph is weakly $2$-colored if the nodes are labeled with colors black and white such that each black node is adjacent to at least one white node and vice versa. In this work we study the distributed computational complexity of weak…

Distributed, Parallel, and Cluster Computing · Computer Science 2019-02-19 Alkida Balliu , Juho Hirvonen , Dennis Olivetti , Jukka Suomela

An odd coloring of a graph $G$ is a proper vertex coloring $\varphi$ with the property that for each non-isolated vertex $v\in V(G)$, there exists a color $c$ such that the cardinality of $\varphi^{-1}(c)\cap N(v)$ is odd. The concept of…

Combinatorics · Mathematics 2024-03-19 S. Kitano

The classic upper bound on the chromatic number of $d$-degenerate graphs is $d+1$, shown to be tight by complete graphs. A natural question is whether this bound remains tight if one forbids large cliques. Classic constructions of Tutte and…

Combinatorics · Mathematics 2026-01-22 Domagoj Bradač , Jacob Fox , Raphael Steiner , Benny Sudakov , Shengtong Zhang

Weak degeneracy is a variation of degeneracy which shares many nice properties of degeneracy. In particular, if a graph $G$ is weakly $d$-degenerate, then for any $(d + 1)$-list assignment $L$ of $G$, one can construct an $L$-coloring of…

Combinatorics · Mathematics 2023-03-15 Ming Han , Tao Wang , Jianglin Wu , Huan Zhou , Xuding Zhu

The generalised colouring numbers $\mathrm{adm}_r(G)$, $\mathrm{col}_r(G)$, and $\mathrm{wcol}_r(G)$ were introduced by Kierstead and Yang as generalisations of the usual colouring number, also known as the degeneracy of a graph, and have…

Discrete Mathematics · Computer Science 2016-06-30 Stephan Kreutzer , Michał Pilipczuk , Roman Rabinovich , Sebastian Siebertz
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