English
Related papers

Related papers: Triangulation Graph and Color Changing Channel

200 papers

A graph $G$ is $(d_1,d_2,d_3)$-colorable if the vertex set $V(G)$ can be partitioned into three subsets $V_1,V_2$ and $V_3$ such that for $i\in\{1,2,3\}$, the induced graph $G[V_i]$ has maximum vertex-degree at most $d_i$. So,…

Combinatorics · Mathematics 2020-01-03 Ligang Jin , Yingli Kang , Peipei Liu , Yingqian Wang

A good deal of research has been done and published on coloring of the vertices of graphs for several years while studying of the excellent work of those maestros, we get inspire to work on the vertex coloring of graphs in case of a…

Discrete Mathematics · Computer Science 2013-09-16 Sabyasachi Mukhopadhyay , Paritosh Bhattacharya , B. B. Ghosh

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

Let G be a plane graph with exactly one triangle T and all other cycles of length at least 5, and let C be a facial cycle of G of length at most six. We prove that a 3-coloring of C does not extend to a 3-coloring of G if and only if C has…

Discrete Mathematics · Computer Science 2017-03-28 Zdenek Dvorak , Dan Kral , Robin Thomas

DP-coloring (also known as correspondence coloring) of a simple graph is a generalization of list coloring. It is known that planar graphs without 4-cycles adjacent to triangles are 4-choosable, and planar graphs without 4-cycles are…

Combinatorics · Mathematics 2017-12-27 Seog-Jin Kim , Xiaowei Yu

A linear coloring of a graph is a proper coloring of the vertices of the graph so that each pair of color classes induce a union of disjoint paths. In this paper, we prove that for every connected graph with maximum degree at most three and…

Combinatorics · Mathematics 2022-12-06 Chun-Hung Liu , Gexin Yu

In the first partial result toward Steinberg's now-disproved three coloring conjecture, Abbott and Zhou used a counting argument to show that every planar graph without cycles of lengths 4 through 11 is 3-colorable. Implicit in their proof…

Combinatorics · Mathematics 2022-09-13 Zachary Hamaker , Vincent Vatter

A rainbow colouring of a connected graph is a colouring of the edges of the graph, such that every pair of vertices is connected by at least one path in which no two edges are coloured the same. Such a colouring using minimum possible…

Discrete Mathematics · Computer Science 2012-05-09 L. Sunil Chandran , Deepak Rajendraprasad

Graph colorings is a fundamental topic in graph theory that require an assignment of labels (or colors) to vertices or edges subject to various constraints. We focus on the harmonious coloring of a graph, which is a proper vertex coloring…

Discrete Mathematics · Computer Science 2021-06-02 Ruxandra Marinescu-Ghemeci , Camelia Obreja , Alexandru Popa

Graph Coloring consists in assigning colors to vertices ensuring that two adjacent vertices do not have the same color. In dynamic graphs, this notion is not well defined, as we need to decide if different colors for adjacent vertices must…

Discrete Mathematics · Computer Science 2025-05-16 Allen Ibiapina , Minh Hang Nguyen , Mikaël Rabie , Cléophée Robin

The precoloring problem of a graph involves assigning colors to some vertices beforehand, and the objective is to determine whether it can be extended to a proper k-coloring of the entire graph. In 1958, Grotzsch proved that every…

Combinatorics · Mathematics 2026-03-09 Xingchao Deng , Beiyan Zou , Hong Zhai

We prove that every cyclically 4-edge-connected cubic graph that can be embedded in the projective plane, with the single exception of the Petersen graph, is 3-edge-colorable. In other words, the only (non-trivial) snark that can be…

Combinatorics · Mathematics 2024-05-28 Yuta Inoue , Ken-ichi Kawarabayashi , Atsuyuki Miyashita , Bojan Mohar , Tomohiro Sonobe

We settle a problem of Havel by showing that there exists an absolute constant d such that if G is a planar graph in which every two distinct triangles are at distance at least d, then G is 3-colorable. In fact, we prove a more general…

Combinatorics · Mathematics 2020-04-16 Zdenek Dvorak , Daniel Kral , Robin Thomas

This paper is concerned with efficiently coloring sparse graphs in the distributed setting with as few colors as possible. According to the celebrated Four Color Theorem, planar graphs can be colored with at most 4 colors, and the proof…

Combinatorics · Mathematics 2019-10-28 Pierre Aboulker , Marthe Bonamy , Nicolas Bousquet , Louis Esperet

A $d$-angulation of a surface is an embedding of a 3-connected graph on that surface that divides it into $d$-gonal faces. A $d$-angulation is said to be Gr\"unbaum colorable if its edges can be $d$-colored so that every face uses all $d$…

Combinatorics · Mathematics 2015-11-10 Serge Lawrencenko , Abdulkarim M. Magomedov

Two colourings of a graph are orthogonal if they have the property that when two vertices are coloured with the same colour in one colouring, then those vertices receive distinct colours in the other colouring. In this paper, orthogonal…

Combinatorics · Mathematics 2020-08-06 Kyle MacKeigan , Jeannette Janssen

A well-studied concept is that of the total chromatic number. A proper total colouring of a graph is a colouring of both vertices and edges so that every pair of adjacent vertices receive different colours, every pair of adjacent edges…

Combinatorics · Mathematics 2010-09-14 Tom Coker , Karen Johannson

We define a method for edge coloring signed graphs and what it means for such a coloring to be proper. Our method has many desirable properties: it specializes to the usual notion of edge coloring when the signed graph is all-negative, it…

Combinatorics · Mathematics 2018-12-05 Richard Behr

Aksenov proved that in a planar graph G with at most one triangle, every precoloring of a 4-cycle can be extended to a 3-coloring of G. We give an exact characterization of planar graphs with two triangles in that some precoloring of a…

Combinatorics · Mathematics 2018-10-25 Zdeněk Dvořák , Bernard Lidický

An $r$-dynamic $k$-coloring of a graph $G$ is a proper $k$-coloring such that for any vertex $v$, there are at least $\min\{r, deg_G(v) \}$ distinct colors in $N_G(v)$. The $r$-dynamic chromatic number $\chi_r^d(G)$ of a graph $G$ is the…

Combinatorics · Mathematics 2019-09-11 Ruijuan Gu , Seog-Jin Kim , Yulai Ma , Yongtang Shi