English
Related papers

Related papers: List coloring the square of sparse graphs with lar…

200 papers

For graphs of bounded maximum average degree, we consider the problem of 2-distance coloring. This is the problem of coloring the vertices while ensuring that two vertices that are adjacent or have a common neighbor receive different…

Discrete Mathematics · Computer Science 2013-01-31 Marthe Bonamy , Benjamin Lévêque , Alexandre Pinlou

Square coloring is a variant of graph coloring where vertices within distance two must receive different colors. When considering planar graphs, the most famous conjecture (Wegner, 1977) states that $\frac32\Delta+1$ colors are sufficient…

Combinatorics · Mathematics 2021-12-24 Nicolas Bousquet , Quentin Deschamps , Lucas de Meyer , Théo Pierron

A graph is $(d_1, \ldots, d_k)$-colorable if its vertex set can be partitioned into $k$ nonempty subsets so that the subgraph induced by the $i$th part has maximum degree at most $d_i$ for each $i\in\{1, \ldots, k\}$. It is known that for…

Combinatorics · Mathematics 2019-08-09 Ilkyoo Choi , Gexin Yu , Xia Zhang

It is shown that any graph with maximum degree $\Delta$ in which the average degree of the induced subgraph on the set of all neighbors of any vertex exceeds $\frac{6k^2}{6k^2 + 1}\Delta + k + 6$ is either $(\Delta - k)$-colorable or…

Combinatorics · Mathematics 2012-10-02 Landon Rabern

In the past various distance based colorings on planar graphs were introduced. We turn our focus to three of them, namely $2$-distance coloring, injective coloring, and exact square coloring. A $2$-distance coloring is a proper coloring of…

Combinatorics · Mathematics 2023-03-20 Hoang La , Kenny Štorgel

We consider the problem of list edge coloring for planar graphs. Edge coloring is the problem of coloring the edges while ensuring that two edges that are incident receive different colors. A graph is k-edge-choosable if for any assignment…

Discrete Mathematics · Computer Science 2013-03-19 Marthe Bonamy

We study squares of planar graphs with the aim to determine their list chromatic number. We present new upper bounds for the square of a planar graph with maximum degree $\Delta \leq 4$. In particular $G^2$ is 5-, 6-, 7-, 8-, 12-,…

Combinatorics · Mathematics 2015-08-06 Daniel W. Cranston , Rok Erman , Riste Škrekovski

A graph $G$ is $(d_1,\ldots,d_k)$-colorable if its vertex set can be partitioned into $k$ sets $V_1,\ldots,V_k$, such that for each $i\in\{1, \ldots, k\}$, the subgraph of $G$ induced by $V_i$ has maximum degree at most $d_i$. The Four…

Combinatorics · Mathematics 2019-03-18 Ilkyoo Choi , Louis Esperet

A strong edge-colouring of a graph is a proper edge-colouring where each colour class induces a matching. It is known that every planar graph with maximum degree $\Delta$ has a strong edge-colouring with at most $4\Delta+4$ colours. We show…

Discrete Mathematics · Computer Science 2014-07-22 Julien Bensmail , Ararat Harutyunyan , Hervé Hocquard , Petru Valicov

The \textit{square} of a graph $G$, denoted by $G^2$, is obtained from $G$ by adding an edge to connect every pair of vertices with a common neighbor in $G$. In this paper we prove that for every planar graph $G$ with maximum degree at most…

Combinatorics · Mathematics 2023-08-15 Jiani Zou , Miaomiao Han , Hong-Jian Lai

A {\em strong edge coloring} of a graph is a proper edge coloring in which every color class is an induced matching. The {\em strong chromatic index} of a graph is the minimum number of colors needed to obtain a strong edge coloring. In an…

Combinatorics · Mathematics 2017-04-17 Watcharintorn Ruksasakchai , Tao Wang

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

Let $G$ be a planar graph without 4-cycles and 5-cycles and with maximum degree $\Delta\ge 32$. We prove that $\chi_{\ell}(G^2)\le \Delta+3$. For arbitrarily large maximum degree $\Delta$, there exist planar graphs $G_{\Delta}$ of girth 6…

Combinatorics · Mathematics 2017-06-14 Daniel W. Cranston , Bobby Jaeger

A graph G is (a:b)-colorable if there exists an assignment of b-element subsets of {1,...,a} to vertices of G such that sets assigned to adjacent vertices are disjoint. We first show that for every triangle-free planar graph G and a vertex…

Combinatorics · Mathematics 2018-09-17 Zdeněk Dvořák , Xiaolan Hu

Total coloring is a variant of edge coloring where both vertices and edges are to be colored. A graph is totally $k$-choosable if for any list assignment of $k$ colors to each vertex and each edge, we can extract a proper total coloring. In…

Discrete Mathematics · Computer Science 2022-12-12 Marthe Bonamy , Théo Pierron , Éric Sopena

For a graph $G$, by $\chi_2(G)$ we denote the minimum integer $k$, such that there is a $k$-coloring of the vertices of $G$ in which vertices at distance at most 2 receive distinct colors. Equivalently, $\chi_2(G)$ is the chromatic number…

Combinatorics · Mathematics 2021-05-25 Mateusz Krzyziński , Paweł Rzążewski , Szymon Tur

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

A 2-distance list k-coloring of a graph is a proper coloring of the vertices where each vertex has a list of at least k available colors and vertices at distance at most 2 cannot share the same color. We prove the existence of a 2-distance…

Combinatorics · Mathematics 2021-05-06 Hoang La

We prove a conjecture of Dvo\v{r}\'ak, Kr\'al, Nejedl\'y, and \v{S}krekovski that planar graphs of girth at least five are square $(\Delta+2)$-colorable for large enough $\Delta$. In fact, we prove the stronger statement that such graphs…

Combinatorics · Mathematics 2019-11-18 Marthe Bonamy , Daniel W. Cranston , Luke Postle

An $i$-independent set is a vertex set whose pairwise distance is at least $i+1$. A proper (square) $k$-coloring of a graph $G$ is a partition of its vertex set into $k$ independent ($2$-independent) sets. A packing $(1^{j}, 2^k)$-coloring…

Combinatorics · Mathematics 2026-04-02 Xujun Liu , Zihui Xu , Xin Zhang
‹ Prev 1 2 3 10 Next ›