English
Related papers

Related papers: Square coloring planar graphs with automatic disch…

200 papers

Using computational techniques we provide a framework for proving results on subclasses of planar graphs via discharging method. The aim of this paper is to apply these techniques to study the 2-distance coloring of planar subcubic graphs.…

Combinatorics · Mathematics 2022-02-15 Hoang La , Petru Valicov

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

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 provide a simplified proof of the following special case of Wegner's conjecture: every planar graph of maximum degree at most three admits a distance-2 coloring with at most eight colors. Our main contribution is significant…

Combinatorics · Mathematics 2025-11-13 Gabriel Elvin , Hajrudin Fejzić , Youngsu Kim

Wegner conjectured in 1977 that the square of every planar graph with maximum degree at most $3$ is $7$-colorable. We prove this conjecture using the discharging method and computational techniques to verify reducible configurations.

Combinatorics · Mathematics 2016-04-25 Stephen G. Hartke , Sogol Jahanbekam , Brent Thomas

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

In this paper we have given a unified graph coloring algorithm for planar graphs. The problems that have been considered in this context respectively, are vertex, edge, total and entire colorings of the planar graphs. The main tool in the…

Combinatorics · Mathematics 2007-11-27 I. Cahit

A vertex coloring of a graph G is called a 2-distance coloring if any two vertices at a distance at most 2 from each other receive different colors. Suppose that G is a planar graph with a maximum degree at most 5. We prove that G admits a…

Combinatorics · Mathematics 2025-08-21 Zakir Deniz

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

We provide a "how-to" guide to the use and application of the Discharging Method. Our aim is not to exhaustively survey results proved by this technique, but rather to demystify the technique and facilitate its wider use, using applications…

Combinatorics · Mathematics 2017-05-15 Daniel W. Cranston , Douglas B. West

In this survey essay, I explore the application of the discharging method in graph theory, including the selection of charging rules and discharging rules, and the general characteristics of the discharging method. As examples, I will prove…

History and Overview · Mathematics 2020-04-16 Haoze Wu

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

it is shown that each triangle-free 1-planar graph with maximum degree $\Delta\geq7$ can be $\Delta$-colorable by Discharging Method.

Combinatorics · Mathematics 2010-12-30 Xin Zhang , Guizhen Liu , Jian-Liang Wu

A vertex coloring of a graph $G$ is called a $2$-distance coloring if any two vertices at a distance at most $2$ from each other receive different colors. Recently, Bousquet et al. (Discrete Mathematics, 346(4), 113288, 2023) proved that…

Combinatorics · Mathematics 2025-12-16 Zakir Deniz

A $2$-distance $k$-coloring of a graph is a proper $k$-coloring of the vertices where vertices at distance at most 2 cannot share the same color. We prove the existence of a $2$-distance ($\Delta+1$)-coloring for graphs with maximum average…

Combinatorics · Mathematics 2021-04-06 Hoang La , Mickael Montassier

The Four color problem is closely related to other branches of mathematics and practical applications. More than 20 of its reformulations are known, which connect this problem with problems of algebra, statistical mechanics and planning.…

History and Overview · Mathematics 2024-05-10 Sergey Kurapov , Maxim Davidovsky

Given a graph $G$ and a list assignment $L(v)$ for each vertex of $v$ of $G$. A proper $L$-list-coloring of $G$ is a function that maps every vertex to a color in $L(v)$ such that no pair of adjacent vertices have the same color. We say…

Combinatorics · Mathematics 2021-09-30 Hoang La , Mickael Montassier

The famous Wegner's Planar Graph Conjecture asserts tight upper bounds on the chromatic number of the square $G^2$ of a planar graph $G$, depending on the maximum degree $\Delta(G)$ of $G$. The only case that the conjecture is resolved is…

Combinatorics · Mathematics 2026-02-17 Eun-Kyung Cho , Ilkyoo Choi , Bernard Lidický

A strong edge coloring of a graph is a proper edge coloring where the edges at distance at most two receive distinct colors. It is known that every planar graph with maximum degree D has a strong edge coloring with at most 4D + 4 colors. We…

Combinatorics · Mathematics 2014-02-24 Dávid Hudák , Borut Lužar , Roman Soták , Riste Škrekovski

A k-distance r-coloring of a graph is a coloring of the vertices of the graph such that if the distance between 2 vertices x and y is less or equal to k, then x and y must have distinct colors. A planar graph is a graph that can be drawn…

Combinatorics · Mathematics 2026-01-21 Sara Al Hajjar
‹ Prev 1 2 3 10 Next ›