English
Related papers

Related papers: Conflict-Free Coloring of String Graphs

200 papers

Given a hypergraph $F$, what is the largest chromatic number that an $F$-free hypergraph can have? In the case of graphs, this question is easy to answer: the chromatic number is unbounded if $F$ contains a cycle, and the largest chromatic…

Combinatorics · Mathematics 2026-04-24 Yichen Wang , Mengyu Duan , Dániel Gerbner , Hilal Hama Karim

An ordered graph $G$ is a graph whose vertex set is a subset of integers. The edges are interpreted as tuples $(u,v)$ with $u < v$. For a positive integer $s$, a matrix $M \in \mathbb{Z}^{s \times 4}$, and a vector $\mathbf{p} =…

Combinatorics · Mathematics 2016-10-05 Maria Axenovich , Jonathan Rollin , Torsten Ueckerdt

In this paper, we study the conflict-free coloring of graphs induced by neighborhoods. A coloring of a graph is conflict-free if every vertex has a uniquely colored vertex in its neighborhood. The conflict-free coloring problem is to color…

Data Structures and Algorithms · Computer Science 2017-10-03 I. Vinod Reddy

A well-studied coloring problem is to assign colors to the edges of a graph $G$ so that, for every pair of vertices, all edges of at least one shortest path between them receive different colors. The minimum number of colors necessary in…

Data Structures and Algorithms · Computer Science 2018-01-17 L. Sunil Chandran , Anita Das , Davis Issac , Erik Jan van Leeuwen

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

Given a graph G, a q-open neighborhood conflict-free coloring or q-ONCF-coloring is a vertex coloring $c:V(G) \rightarrow \{1,2,\ldots,q\}$ such that for each vertex $v \in V(G)$ there is a vertex in $N(v)$ that is uniquely colored from the…

Computational Complexity · Computer Science 2019-05-02 Hans L. Bodlaender , Sudeshna Kolay , Astrid Pieterse

In an undirected graph, a conflict-free coloring (with respect to open neighborhoods) is an assignment of colors to the vertices of the graph $G$ such that every vertex in $G$ has a uniquely colored vertex in its open neighborhood. The…

Discrete Mathematics · Computer Science 2019-10-03 Sriram Bhyravarapu , Subrahmanyam Kalyanasundaram

A dynamic coloring of a graph $G$ is a proper coloring such that for every vertex $v\in V(G)$ of degree at least 2, the neighbors of $v$ receive at least 2 colors. In this paper we present some upper bounds for the dynamic chromatic number…

Combinatorics · Mathematics 2009-08-19 Meysam Alishahi

A path in an(a) edge(vertex)-colored graph is called \emph{a conflict-free path} if there exists a color used on only one of its edges(vertices). An(A) edge(vertex)-colored graph is called \emph{conflict-free (vertex-)connected} if there is…

Combinatorics · Mathematics 2018-09-20 Meng Ji , Xueliang Li , Xiaoyu Zhu

A proper coloring $\phi$ of $G$ is called a proper conflict-free coloring of $G$ if for every non-isolated vertex $v$ of $G$, there is a color $c$ such that $|\phi^{-1}(c)\cap N_G(v)|=1$. As an analogy to degree-choosability of graphs, the…

Combinatorics · Mathematics 2025-09-09 Masaki Kashima , Riste Škrekovski , Rongxing Xu

Let $G$ be a graph with $n$ vertices, $m$ edges, average degree $\delta$, and maximum degree $\Delta$. The "oriented chromatic number" of $G$ is the maximum, taken over all orientations of $G$, of the minimum number of colours in a proper…

Combinatorics · Mathematics 2008-09-09 David R. Wood

A {\em conflict-free coloring} of a graph {\em with respect to open} (resp., {\em closed}) {\em neighborhood} is a coloring of vertices such that for every vertex there is a color appearing exactly once in its open (resp., closed)…

Combinatorics · Mathematics 2022-10-11 Igor Fabrici , Borut Lužar , Simona Rindošová , Roman Soták

Recently, it was proved that triangle-free intersection graphs of $n$ line segments in the plane can have chromatic number as large as $\Theta(\log\log n)$. Essentially the same construction produces $\Theta(\log\log n)$-chromatic…

Computational Geometry · Computer Science 2014-12-30 Tomasz Krawczyk , Arkadiusz Pawlik , Bartosz Walczak

A graph $G$ is conflict-free $k$-edge-colorable if there exists an assignment of $k$ colors to $E(G)$ such that for every edge $e\in E(G)$, there is a color that is assigned to exactly one edge among the closed neighborhood of $e$. The…

Discrete Mathematics · Computer Science 2024-09-25 Shanshan Guo , Ethan Y. H. Li , Luyi Li , Ping Li

A path in a vertex-colored graph is called {\it conflict-free} if there is a color used on exactly one of its vertices. A vertex-colored graph is said to be {\it conflict-free vertex-connected} if any two vertices of the graph are connected…

Combinatorics · Mathematics 2017-09-06 Zhenzhen Li , Baoyindureng Wu

An \emph{odd $c$-coloring} of a graph is a proper $c$-coloring such that each non-isolated vertex has a color appearing an odd number of times within its open neighborhood. A \emph{proper conflict-free $c$-coloring} of a graph is a proper…

Combinatorics · Mathematics 2025-02-26 Tao Wang , Xiaojing Yang

An edge-colored graph $G$ is conflict-free connected if any two of its vertices are connected by a path which contains a color used on exactly one of its edges. The conflict-free connection number of a connected graph $G$, denoted by…

Combinatorics · Mathematics 2018-09-12 Ran Gu , Xueliang Li

We study a new variant of graph coloring by adding a connectivity constraint. A path in a vertex-colored graph is called conflict-free if there is a color that appears exactly once on its vertices. A connected graph $G$ is said to be…

Computational Complexity · Computer Science 2024-08-15 Sun-Yuan Hsieh , Hoang-Oanh Le , Van Bang Le , Sheng-Lung Peng

A vertex-coloring of a connected graph $G$ is a strong conflict-free vertex-connection coloring if every two distinct vertices are joined by a shortest path on which some color appears exactly once. The minimum number of colors in such a…

Discrete Mathematics · Computer Science 2026-05-14 Samuel German

A vertex-coloring of a hypergraph is conflict-free, if each edge contains a vertex whose color is not repeated on any other vertex of that edge. Let $f(r, \Delta)$ be the smallest integer $k$ such that each $r$-uniform hypergraph of maximum…

Combinatorics · Mathematics 2016-12-06 Maria Axenovich , Jonathan Rollin