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In this paper, we present a foundation study for proper colouring of edge-set graphs. The authors consider that a detailed study of the colouring of edge-set graphs corresponding to the family of paths is best suitable for such foundation…

General Mathematics · Mathematics 2018-05-08 Johan Kok , Sudev Naduvath

A proper vertex colouring of a graph is \emph{nested} if the vertices of each of its colour classes can be ordered by inclusion of their open neighbourhoods. Through a relation to partially ordered sets, we show that the nested chromatic…

Combinatorics · Mathematics 2013-06-04 David Cook

An equation is called graph-regular if it always has monochromatic solutions under edge-colorings of the complete graph on the naturals. We present two Rado-like conditions which are respectively necessary and sufficient for an equation to…

Combinatorics · Mathematics 2012-02-14 Andy Parrish

An interval coloring of a graph G is a proper coloring of E(G) by positive integers such that the colors on the edges incident to any vertex are consecutive. A (3,4)-biregular bigraph is a bipartite graph in which each vertex of one part…

Combinatorics · Mathematics 2007-05-23 Armen S. Asratian , Carl Johan Casselgren , Jennifer Vandenbussche , Douglas B. West

A vertex colouring of a graph is called asymmetric if the only automorphism which preserves it is the identity. Tucker conjectured that if every automorphism of a connected, locally finite graph moves infinitely many vertices, then there is…

Combinatorics · Mathematics 2020-07-21 Florian Lehner , Monika Pilśniak , Marcin Stawiski

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 the problem of existence of perfect $2$-colorings (equitable $2$-partitions) of Hamming graphs with given parameters. We start with conditions on parameters of graphs and colorings that are necessary for their existence. Next we…

Given a graph on $n$ vertices and an assignment of colours to the edges, a rainbow Hamilton cycle is a cycle of length $n$ visiting each vertex once and with pairwise different colours on the edges. Similarly (for even $n$) a rainbow…

Combinatorics · Mathematics 2016-02-17 Deepak Bal , Patrick Bennett , Xavier Pérez-Giménez , Paweł Prałat

In this paper we describe all edge-colored graphs that are fully symmetric with respect to colors and transitive on every set of edges of the same color. They correspond to fully symmetric homogeneous factorizations of complete graphs. Our…

Combinatorics · Mathematics 2012-01-24 Mariusz Grech , Andrzej Kisielewicz

Motivated by the definition of linear coloring on simplicial complexes, recently introduced in the context of algebraic topology \cite{Civan}, and the framework through which it was studied, we introduce the linear coloring on graphs. We…

Discrete Mathematics · Computer Science 2008-07-29 Kyriaki Ioannidou , Stavros D. Nikolopoulos

An incidence of a graph $G$ is a vertex-edge pair $(v,e)$ such that $v$ is incidence with $e$. A conflict-free incidence coloring of a graph is a coloring of the incidences in such a way that two incidences $(u,e)$ and $(v,f)$ get distinct…

Combinatorics · Mathematics 2022-10-11 Mengke Qi , Xin Zhang

In this short paper, we introduce a new vertex coloring whose motivation comes from our series on odd edge-colorings of graphs. A proper vertex coloring $\varphi$ of graph $G$ is said to be odd if for each non-isolated vertex $x\in V(G)$…

Combinatorics · Mathematics 2022-07-01 Mirko Petruševski , Riste Škrekovski

Let $C$ be a cycle and $f : V(C) \rightarrow \{c_1,c_2,\ldots,c_k\}$ a proper $k$-colouring of $C$ for some $k \ge 4$. We say the colouring $f$ is safe if for any planar graph $G$ in which $C$ is an induced cycle, there exists a proper…

Combinatorics · Mathematics 2023-06-09 Ajit Diwan

A proper conflict-free coloring of a graph is a proper vertex coloring wherein each non-isolated vertex's open neighborhood contains at least one color appearing exactly once. For a non-negative integer $k$, a graph $G$ is said to be proper…

Combinatorics · Mathematics 2025-12-30 Yuting Wang , Xin Zhang

An $i$-independent set is a set of vertices whose pairwise distance is at least $i+1$. A proper coloring (resp. a square coloring) of a graph is a partition of its vertices into independent (resp. $2$-independent) sets. A packing…

Combinatorics · Mathematics 2025-09-04 Ilkyoo Choi , Xujun Liu

An adjacent vertex distinguishing edge colouring of a graph $G$ without isolated edges is its proper edge colouring such that no pair of adjacent vertices meets the same set of colours in $G$. We show that such colouring can be chosen from…

Combinatorics · Mathematics 2019-01-08 Jakub Kwaśny , Jakub Przybyło

An incidence in a graph $G$ is a pair $(v,e)$ where $v$ is a vertex of $G$ and $e$ is an edge of $G$ incident to $v$. Two incidences $(v,e)$ and $(u,f)$ are adjacent if at least one of the following holds: $(a)$ $v = u$, $(b)$ $e = f$, or…

Combinatorics · Mathematics 2016-08-08 Petr Gregor , Borut Lužar , Roman Soták

Given an edge colouring of a graph with a set of $m$ colours, we say that the graph is (exactly) $m$-coloured if each of the colours is used. We consider edge colourings of the complete graph on $\mathbb{N}$ with infinitely many colours and…

Combinatorics · Mathematics 2016-09-07 Teeradej Kittipassorn , Bhargav Narayanan

In graph coloring problems, the goal is to assign a positive integer color to each vertex of an input graph such that adjacent vertices do not receive the same color assignment. For classic graph coloring, the goal is to minimize the…

Data Structures and Algorithms · Computer Science 2016-10-11 Joan Boyar , Leah Epstein , Lene M. Favrholdt , Kim S. Larsen , Asaf Levin

A total coloring of a graph $G$ is a coloring of its vertices and edges such that no adjacent vertices, edges, and no incident vertices and edges obtain the same color. An \emph{interval total $t$-coloring} of a graph $G$ is a total…

Discrete Mathematics · Computer Science 2010-10-15 P. A. Petrosyan , A. Yu. Torosyan , N. A. Khachatryan