English
Related papers

Related papers: Mrs. Correct and Majority Colorings

200 papers

Consider edge colorings of digraphs where edges $v_1 v_2$ and $v_2 v_3$ have different colors. This coloring induces a vertex coloring by sets of edge colors, in which edge $v_1 v_2$ in the graph implies that the set color of $v_1$ contains…

Combinatorics · Mathematics 2024-07-10 Seth Chaiken

For a positive integer $k$, a $k$-colouring of a graph $G=(V,E)$ is a mapping $c: V\rightarrow\{1,2,...,k\}$ such that $c(u)\neq c(v)$ whenever $uv\in E$. The Colouring problem is to decide, for a given $G$ and $k$, whether a $k$-colouring…

Computational Complexity · Computer Science 2016-02-16 Petr A. Golovach , Matthew Johnson , Daniël Paulusma , Jian Song

Defective coloring (also known as relaxed or improper coloring) is a generalization of proper coloring defined as follows: for $d \in \mathbb{N}$, a coloring of a graph is $d$-defective if every vertex is colored the same as at most $d$ of…

Combinatorics · Mathematics 2024-11-26 James Anderson

A simple but empirically efficient heuristic algorithm for the edge-coloring of graphs is presented. Its basic idea is the displacement of "conflicts" (repeated colors in the edges incident to a vertex) along paths of adjacent vertices…

Combinatorics · Mathematics 2012-10-19 M. A. Fiol , J. Vilaltella

Defective coloring is a variant of traditional vertex-coloring, according to which adjacent vertices are allowed to have the same color, as long as the monochromatic components induced by the corresponding edges have a certain structure.…

Data Structures and Algorithms · Computer Science 2016-03-24 Patrizio Angelini , Michael A. Bekos , Michael Kaufmann , Vincenzo Roselli

In many practical applications the underlying graph must be as equitable colored as possible. A coloring is called equitable if the number of vertices colored with each color differs by at most one, and the least number of colors for which…

Combinatorics · Mathematics 2021-07-01 Emanuel Florentin Olariu , Cristian Frasinaru

A proper edge $t$-coloring of a graph is a coloring of its edges with colors $1,2,...,t$ such that all colors are used, and no two adjacent edges receive the same color. For any integer $n\geq 3$, all possible values of $t$ are found, for…

Discrete Mathematics · Computer Science 2012-05-02 R. R. Kamalian

We investigate proper $(a:b)$-fractional colorings of $n$-uniform hypergraphs, which generalize traditional integer colorings of graphs. Each vertex is assigned $b$ distinct colors from a set of $a$ colors, and an edge is properly colored…

Combinatorics · Mathematics 2025-04-18 Margarita Akhmejanova , Sean Longbrake

In the paper we apply graph vertex coloring for verification of secret shares. We start from showing how to convert any graph into the number and vice versa. Next, theoretical result concerning properties of n-colorable graphs is stated and…

Cryptography and Security · Computer Science 2007-05-23 Kamil Kulesza , Zbigniew Kotulski

A proper coloring of a graph is \emph{conflict-free} if, for every non-isolated vertex, some color is used exactly once on its neighborhood. Caro, Petru\v{s}evski, and \v{S}krekovski proved that every graph $G$ has a proper conflict-free…

Combinatorics · Mathematics 2024-12-16 Daniel W. Cranston , Chun-Hung Liu

We consider vertex coloring of an acyclic digraph $\Gdag$ in such a way that two vertices which have a common ancestor in $\Gdag$ receive distinct colors. Such colorings arise in a natural way when bounding space for various genetic data…

Combinatorics · Mathematics 2007-06-12 Geir Agnarsson , Agust Egilsson , Magnus Mar Halldorsson

An adjacent vertex distinguishing total $k$-coloring $f$ of a graph $G$ is a proper total $k$-coloring of $G$ such that no pair of adjacent vertices has the same color sets, where the color set at a vertex $v$, $C^G_f(v)$, is $\{f(v)\} \cup…

Combinatorics · Mathematics 2022-08-24 Hanna Furmańczyk , Rita Zuazua

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

We show that, given an infinite cardinal $\mu$, a graph has colouring number at most $\mu$ if and only if it contains neither of two types of subgraph. We also show that every graph with infinite colouring number has a well-ordering of its…

Combinatorics · Mathematics 2018-07-05 Nathan Bowler , Johannes Carmesin , Péter Komjáth , Christian Reiher

The classical theorem of Vizing states that every graph of maximum degree $d$ admits an edge-coloring with at most $d+1$ colors. Furthermore, as it was earlier shown by K\H{o}nig, $d$ colors suffice if the graph is bipartite. We investigate…

Combinatorics · Mathematics 2016-08-23 Endre Csóka , Gabor Lippner , Oleg Pikhurko

A \textit{rainbow subgraph} of an edge-colored graph is a subgraph whose edges have distinct colors. The \textit{color degree} of a vertex $v$ is the number of different colors on edges incident to $v$. We show that if $n$ is large enough…

Combinatorics · Mathematics 2012-04-17 Alexandr Kostochka , Florian Pfender , Matthew Yancey

A harmonious coloring of a $k$-uniform hypergraph $H$ is a vertex coloring such that no two vertices in the same edge have the same color, and each $k$-element subset of colors appears on at most one edge. The harmonious number $h(H)$ is…

Combinatorics · Mathematics 2024-08-07 Sebastian Czerwiński

Independently posed by Behzad and Vizing, the Total Coloring Conjecture asserts that the total chromatic number of a simple connected graph $G$ is either $\Delta(G)+1$ or $\Delta(G)+2$, where $\Delta(G)$ is the largest degree of any vertex…

Combinatorics · Mathematics 2026-05-13 I. J. Dejter

The \emph{chromatic number} of a directed graph $D$ is the minimum number of colors needed to color the vertices of $D$ such that each color class of $D$ induces an acyclic subdigraph. Thus, the chromatic number of a tournament $T$ is the…

Combinatorics · Mathematics 2017-03-16 Ararat Harutyunyan , Tien-Nam Le , Stéphan Thomassé , Hehui Wu

We confirm the equitable $\Delta$-coloring conjecture for interval graphs and establish the monotonicity of equitable colorability for them. We further obtain results on equitable colorability about square (or Cartesian) and cross (or…

Combinatorics · Mathematics 2009-03-10 Bor-Liang Chen , Ko-Wei Lih , Jing-Ho Yan