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Related papers: Coloring locally sparse graphs

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Fix $\varepsilon>0$ and a nonnull graph $H$. A well-known theorem of R\"odl from the 80s says that every graph $G$ with no induced copy of $H$ contains a linear-sized $\varepsilon$-restricted set $S\subseteq V(G)$, which means $S$ induces a…

Combinatorics · Mathematics 2023-07-21 Tung H. Nguyen

A total $k$-coloring of a graph $G$ is a coloring of $V(G)\cup E(G)$ using $k$ colors such that no two adjacent or incident elements receive the same color. The total chromatic number $\chi"(G)$ of $G$ is the smallest integer $k$ such that…

Combinatorics · Mathematics 2021-12-28 Fan Yang , Jianliang Wu

The \emph{local boxicity} of a graph $G$, denoted by $lbox(G)$, is the minimum positive integer $l$ such that $G$ can be obtained using the intersection of $k$ (, where $k \geq l$,) interval graphs where each vertex of $G$ appears as a…

Combinatorics · Mathematics 2022-01-26 Atrayee Majumder , Rogers Mathew

The closed neighbourhood $N[v]$ of a vertex $v$ of a graph $G$, consisting of at least one vertex from all colour classes with respect to a proper colouring of $G$, is called a rainbow neighbourhood in $G$. The minimum number of vertices…

General Mathematics · Mathematics 2017-11-13 Johan Kok , Sudev Naduvath , Eunice Gogo Mphako-Banda

A proper total $k$-colouring of a graph $G=(V,E)$ is an assignment $c : V \cup E\to \{1,2,\ldots,k\}$ of colours to the edges and the vertices of $G$ such that no two adjacent edges or vertices and no edge and its end-vertices are…

Combinatorics · Mathematics 2018-03-08 Hervé Hocquard , Jakub Przybyło

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 graph G is (d_1,..,d_l)-colorable if the vertex set of G can be partitioned into subsets V_1,..,V_l such that the graph G[V_i] induced by the vertices of V_i has maximum degree at most d_i for all 1 <= i <= l. In this paper, we focus on…

Combinatorics · Mathematics 2013-06-06 Mickael Montassier , Pascal Ochem

A multigraph $G = (V, E)$ is $(k, \ell)$-sparse if every subset $X \subseteq V$ induces at most $\max\{k|X| - \ell, 0\}$ edges. Finding a maximum-size $(k, \ell)$-sparse subgraph is a classical problem in rigidity theory and combinatorial…

Data Structures and Algorithms · Computer Science 2025-11-24 Péter Madarasi

The square $G^2$ of a graph $G$ is the graph defined on $V(G)$ such that two vertices $u$ and $v$ are adjacent in $G^2$ if the distance between $u$ and $v$ in $G$ is at most 2. The {\em maximum average degree} of $G$, $mad (G)$, is the…

Combinatorics · Mathematics 2015-06-16 Seog-Jin Kim , Boram Park

In the noisy channel model from coding theory, we wish to detect errors introduced during transmission by optimizing various parameters of the code. Bennett, Dudek, and LaForge framed a variation of this problem in the language of…

Combinatorics · Mathematics 2020-01-28 Patrick Bennett , Ryan Cushman , Andrzej Dudek

A strong $k$-edge-coloring of a graph G is an edge-coloring with $k$ colors in which every color class is an induced matching. The strong chromatic index of $G$, denoted by $\chi'_{s}(G)$, is the minimum $k$ for which $G$ has a strong…

Combinatorics · Mathematics 2018-09-11 Tianjiao Dai , Guanghui Wang , Donglei Yang , Gexin Yu

A locally irregular multigraph is a multigraph whose adjacent vertices have distinct degrees. The locally irregular edge coloring is an edge coloring of a multigraph $G$ such that every color induces a locally irregular submultigraph of…

Combinatorics · Mathematics 2022-08-19 Igor Grzelec , Mariusz Woźniak

For a proper vertex coloring $c$ of a graph $G$, let $\varphi_c(G)$ denote the maximum, over all induced subgraphs $H$ of $G$, the difference between the chromatic number $\chi(H)$ and the number of colors used by $c$ to color $H$. We…

Combinatorics · Mathematics 2014-11-19 N. R. Aravind , Subrahmanyam Kalyanasundaram , R. B. Sandeep , Naveen Sivadasan

A $k$-proper edge-coloring of a graph G is called adjacent vertex-distinguishing if any two adjacent vertices are distinguished by the set of colors appearing in the edges incident to each vertex. The smallest value $k$ for which $G$ admits…

Discrete Mathematics · Computer Science 2022-01-05 Sylvain Gravier , Hippolyte Signargout , Souad Slimani

For an undirected, simple, finite, connected graph $G$, we denote by $V(G)$ and $E(G)$ the sets of its vertices and edges, respectively. A function $\varphi:E(G)\rightarrow \{1,...,t\}$ is called a proper edge $t$-coloring of a graph $G$,…

Combinatorics · Mathematics 2013-07-05 A. M. Khachatryan , R. R. Kamalian

In the Densest k-Subgraph problem, given a graph G and a parameter k, one needs to find a subgraph of G induced on k vertices that contains the largest number of edges. There is a significant gap between the best known upper and lower…

Data Structures and Algorithms · Computer Science 2010-01-19 Aditya Bhaskara , Moses Charikar , Eden Chlamtac , Uriel Feige , Aravindan Vijayaraghavan

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

Let $G=(V,E)$ be a multigraph of maximum degree $\Delta$. The edges of $G$ can be colored with at most $\frac{3}{2}\Delta$ colors by Shannon's theorem. We study lower bounds on the size of subgraphs of $G$ that can be colored with $\Delta$…

Data Structures and Algorithms · Computer Science 2013-09-25 Michał Farnik , Łukasz Kowalik , Arkadiusz Socała

An adjacent vertex distinguishing coloring of a graph G is a proper edge coloring of G such that any pair of adjacent vertices are incident with distinct sets of colors. The minimum number of colors needed for an adjacent vertex…

Combinatorics · Mathematics 2012-08-14 Lianzhu Zhang , Weifan Wang , Ko-Wei Lih

A triangle in a hypergraph $\mathcal{H}$ is a set of three distinct edges $e, f, g\in\mathcal{H}$ and three distinct vertices $u, v, w\in V(\mathcal{H})$ such that $\{u, v\}\subseteq e$, $\{v, w\}\subseteq f$, $\{w, u\}\subseteq g$ and…

Combinatorics · Mathematics 2025-08-25 Lina Li , Luke Postle