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Related papers: Extended core and choosability of a graph

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An edge-coloring of a graph $G$ with colors $1,\ldots,t$ is an interval $t$-coloring if all colors are used, and the colors of edges incident to each vertex of $G$ are distinct and form an interval of integers. A graph $G$ is interval…

Discrete Mathematics · Computer Science 2016-04-01 Hrant Khachatrian , Tigran Mamikonyan

An {\em odd subgraph} of a graph is a subgraph in which every vertex has odd degree. A graph $G$ is said to be {\em odd $k$-edge-colorable} if there exists an edge-coloring $E(G) \rightarrow \{1,2, \ldots, k\}$ such that each non-empty…

Combinatorics · Mathematics 2026-04-20 Mikio Kano , Shun-ichi Maezawa , Kenta Ozeki

We study relations between three interrelated notions of graph (list) coloring: single conflict coloring, adapted list coloring and choosability with separation (with $1$ overlapping color between lists of adjacent vertices), and their…

Combinatorics · Mathematics 2025-09-18 Carl Johan Casselgren , Kalle Eriksson

For a number $l\geq 2$, let ${\cal{G}}_l$ denote the family of graphs which have girth $2l+1$ and have no odd hole with length greater than $2l+1$. Wu, Xu and Xu conjectured that every graph in $\bigcup_{l\geq 2} {\cal{G}}_{l}$ is…

Combinatorics · Mathematics 2023-07-06 Yan Wang , Rong Wu

A graph is $(k_1,k_2)$-colorable if its vertex set can be partitioned into a graph with maximum degree at most $k_1$ and and a graph with maximum degree at most $k_2$. We show that every $(C_3,C_4,C_6)$-free planar graph is…

Discrete Mathematics · Computer Science 2017-11-27 François Dross , Pascal Ochem

As one of the first applications of the polynomial method in combinatorics, Alon and Tarsi gave a way to prove that a graph is choosable (colorable from any lists of prescribed size). We describe an efficient way to implement this approach,…

Discrete Mathematics · Computer Science 2023-01-18 Zdeněk Dvořák

In this work, we continue the study of vertex colorings of graphs, in which adjacent vertices are allowed to be of the same color as long as each monochromatic connected component is of relatively small cardinality. We focus on colorings…

Data Structures and Algorithms · Computer Science 2019-12-03 Michael A. Bekos , Carla Binucci , Michael Kaufmann , Chrysanthi Raftopoulou , Antonios Symvonis , Alessandra Tappini

We say that a graph $G$ is chromatic-choosable when its list chromatic number $\chi_{\ell}(G)$ is equal to its chromatic number $\chi(G)$. Chromatic-choosability is a well-studied topic, and in fact, some of the most famous results and…

A (1,{\lambda})-embedded graph is a graph that can be embedded on a surface with Euler characteristic {\lambda} so that each edge is crossed by at most one other edge. A graph G is called {\alpha}-linear if there exists an integral constant…

Combinatorics · Mathematics 2011-12-08 Xin Zhang , Guizhen Liu , Jian-Liang Wu

A graph is $1$-$planar$ if it can be drawn in the plane so that each edge is crossed by at most one other edge. Moreover, a 1-planar graph $G$ is $optimal$ if it satisfies $|E(G)|=4|V(G)|-8$. J. Fujisawa et al. [16] first considered…

Combinatorics · Mathematics 2022-05-25 Jiangyue Zhang , Yan Wu , Heping Zhang

A $(c_1,c_2,...,c_k)$-coloring of $G$ is a mapping $\varphi:V(G)\mapsto\{1,2,...,k\}$ such that for every $i,1 \leq i \leq k$, $G[V_i]$ has maximum degree at most $c_i$, where $G[V_i]$ denotes the subgraph induced by the vertices colored…

Combinatorics · Mathematics 2014-09-29 Runrun Liu , Xiangwen Li , Gexin Yu

A decomposition of a graph $G$ is a family of subgraphs of $G$ whose edge sets form a partition of $E(G)$. In this paper, we prove that every triangle-free planar graph $G$ can be decomposed into a $2$-degenerate graph and a matching.…

Combinatorics · Mathematics 2022-12-15 Rongxing Xu , Xuding Zhu

Given positive integers $k \leq m$ and a graph $G$, a family of lists $L = \{L(v) : v \in V(G)\}$ is said to be a random $(k,m)$-list-assignment if for every $v \in V(G)$ the list $L(v)$ is a subset of $\{1, \ldots, m\}$ of size $k$, chosen…

Combinatorics · Mathematics 2024-04-10 Dan Hefetz , Michael Krivelevich

A graph $G$ is \emph{$(a,b)$-choosable} if given any list assignment $L$ with $|L(v)|=a$ for each $v\in V(G)$ there exists a function $\varphi$ such that $\varphi(v)\in L(v)$ and $|\varphi(v)|=b$ for all $v\in V(G)$, and whenever vertices…

Combinatorics · Mathematics 2019-11-18 Daniel W. Cranston

A b-coloring is a coloring of the vertices of a graph such that each color class contains a vertex that has a neighbor in all other color classes, and the b-chromatic number of a graph $G$ is the largest integer $k$ such that $G$ admits a…

Discrete Mathematics · Computer Science 2012-12-13 Chinh T. Hoàng , Frédéric Maffray , Meriem Mechebbek

A proper $s$-coloring of an $n$-vertex graph is \emph{equitable} if every color class has size $\lfloor{n/s}\rfloor$ or $\lceil{n/s}\rceil$. A necessary condition to have an equitable $s$-coloring is that every vertex $v$ appears in an…

Combinatorics · Mathematics 2025-09-23 Daniel W. Cranston , Reem Mahmoud

A graph is $(d_1, ..., d_r)$-colorable if its vertex set can be partitioned into $r$ sets $V_1, ..., V_r$ so that the maximum degree of the graph induced by $V_i$ is at most $d_i$ for each $i\in \{1, ..., r\}$. For a given pair $(g, d_1)$,…

Combinatorics · Mathematics 2014-12-02 Hojin Choi , Ilkyoo Choi , Jisu Jeong , Geewon Suh

In this article, we use a unified approach to prove several classes of planar graphs are DP-$3$-colorable, which extend the corresponding results on $3$-choosability.

Combinatorics · Mathematics 2018-09-20 Runrun Liu , Sarah Loeb , Yuxue Yin , Gexin Yu

A graph $G$ is list point $k$-arborable if, whenever we are given a $k$-list assignment $L(v)$ of colors for each vertex $v\in V(G)$, we can choose a color $c(v)\in L(v)$ for each vertex $v$ so that each color class induces an acyclic…

Combinatorics · Mathematics 2014-03-13 Xin Zhang

Given a graph $G$ and a mapping $f:V(G) \to \mathbb{N}$, an $f$-list assignment of $G$ is a function that maps each $v \in V(G)$ to a set of at least $f(v)$ colors. For an $f$-list assignment $L$ of a graph $G$, a proper conflict-free…

Combinatorics · Mathematics 2026-01-23 Masaki Kashima , Riste Škrekovski , Rongxing Xu