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Related papers: Some results on minimum skew zero forcing sets, an…

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Let $H=(V(H),E(H))$ be a graph. A $k$-coloring of $H$ is a mapping $\pi : V(H) \longrightarrow \{1,2,\ldots, k\}$ so that each color class induces a $K_2$-free subgraph. For a graph $G$ of order at least $2$, a $G$-free $k$-coloring of $H$…

Combinatorics · Mathematics 2022-01-21 Yaser Rowshan

Motivated by a conjecture from the automated conjecturing program TxGraffiti, in this paper the relationship between the zero forcing number, $Z(G)$, and the vertex independence number, $\alpha(G)$, of cubic and subcubic graphs is explored.…

Combinatorics · Mathematics 2024-11-04 Houston Schuerger , Nathan Warnberg , Michael Young

A graph in which all minimal zero forcing sets are in fact minimum size is called ``well-forced." This paper characterizes well-forced trees and presents an algorithm for determining which trees are well-forced. Additionally, we…

Combinatorics · Mathematics 2023-12-25 Cheryl Grood , Ruth Haas , Bonnie Jacob , Erika King , Shahla Nasserasr

In the minimum sum edge coloring problem, we aim to assign natural numbers to edges of a graph, so that adjacent edges receive different numbers, and the sum of the numbers assigned to the edges is minimum. The {\em chromatic edge strength}…

Discrete Mathematics · Computer Science 2008-01-22 Jean Cardinal , Vlady Ravelomanana , Mario Valencia-Pabon

Let $G=(V,E)$ be a graph. A subset $D\subseteq V$ is a dominating set if every vertex not in $D$ is adjacent to a vertex in $D$. A dominating set $D$ is called a total dominating set if every vertex in $D$ is adjacent to a vertex in $D$.…

Combinatorics · Mathematics 2011-09-09 Fu-Tao Hu , Jun-Ming Xu

Probabilistic zero forcing is a coloring game played on a graph where the goal is to color every vertex blue starting with an initial blue vertex set. As long as the graph is connected, if at least one vertex is blue then eventually all of…

Combinatorics · Mathematics 2022-01-13 Shyam Narayanan , Alec Sun

We give an algorithm that finds a zero forcing set which approximates the optimal size by a factor of $\text{pw}(G)+1$, where $\text{pw}(G)$ is the pathwidth of $G$. Starting from a path decomposition, the algorithm runs in $O(nm)$ time,…

Combinatorics · Mathematics 2024-02-15 Ben Cameron , Jeannette Janssen , Rogers Matthew , Zhiyuan Zhang

Given a set $\mathcal{F}$ of graphs, a graph $G$ is $\mathcal{F}$-free if $G$ does not contain any member of $\mathcal{F}$ as an induced subgraph. Barrus, Kumbhat, and Hartke [M. D. Barrus, M. Kumbhat, and S. G. Hartke, Graph classes…

Combinatorics · Mathematics 2015-08-04 Michael D. Barrus , Stephen G. Hartke

Call a graph $G$ zero-forcing for a finite abelian group $\mathcal{G}$ if for every $\ell : V(G) \to \mathcal{G}$ there is a connected $A \subseteq V(G)$ with $\sum_{a \in A} \ell(a) = 0$. The problem we pose here is to characterise the…

Combinatorics · Mathematics 2016-10-17 Daniel Weißauer

Zero forcing is a coloring game played on a graph that was introduced more than ten years ago in several different applications. The goal is to color all the vertices blue by repeated use of a (deterministic) color change rule.…

Combinatorics · Mathematics 2018-12-31 Jesse Geneson , Leslie Hogben

Zero forcing is a propagation process on a graph, or digraph, defined in linear algebra to provide a bound for the minimum rank problem. Independently, zero forcing was introduced in physics, computer science and network science, areas…

Combinatorics · Mathematics 2019-03-28 Daniela Ferrero , Thomas Kalinowski , Sudeep Stephen

We introduce randomized zero forcing (RZF), a stochastic color-change process on directed graphs in which a white vertex turns blue with probability equal to the fraction of its incoming neighbors that are blue. Unlike probabilistic zero…

Combinatorics · Mathematics 2026-02-19 Jesse Geneson , Illya Hicks , Noah Lichtenberg , Alvin Moon , Nicolas Robles

In this paper we compare the brushing number of a graph with the zero-forcing number of its line graph. We prove that the zero-forcing number of the line graph is an upper bound for the brushing number by constructing a brush configuration…

Combinatorics · Mathematics 2020-08-25 Aras Erzurumluoglu , David Pike , Karen Meagher

The minimum skew rank of a simple graph G over the field of real numbers, is the smallest possible rank among all real skew-symmetric matrices whose (i,j)-entry (for i not equal to j) is nonzero whenever {i, j} is an edge in G and is zero…

Combinatorics · Mathematics 2011-07-13 Luz M. DeAlba

Let $G=(V(G), E(G))$ be a graph with maximum degree $\Delta$. For a subset $M$ of $E(G)$, we denote by $G[V(M)]$ the subgraph of $G$ induced by the endvertices of edges in $M$. We call $M$ a semistrong matching if each edge of $M$ is…

Combinatorics · Mathematics 2023-10-20 Yuquan Lin , Wensong Lin

A vertex coloring of a graph is said to be \textit{conflict-free} with respect to neighborhoods if for every non-isolated vertex there is a color appearing exactly once in its (open) neighborhood. As defined in [Fabrici et al.,…

Combinatorics · Mathematics 2022-03-03 Yair Caro , Mirko Petruševski , Riste Škrekovski

Coloring a graph $G$ consists in finding an assignment of colors $c: V(G)\to\{1,\ldots,p\}$ such that any pair of adjacent vertices receives different colors. The minimum integer $p$ such that a coloring exists is called the chromatic…

Discrete Mathematics · Computer Science 2019-12-25 Théo Pierron

In this paper, controllability of systems defined on graphs is discussed. We consider the problem of controllability of the network for a family of matrices carrying the structure of an underlying directed graph. A one-to-one correspondence…

Systems and Control · Computer Science 2014-03-20 Nima Monshizadeh , Shuo Zhang , Kanat Camlibel

The minimum forcing number of a graph $G$ is the smallest number of edges simultaneously contained in a unique perfect matching of $G$. Zhang, Ye and Shiu \cite{HDW} showed that the minimum forcing number of any fullerene graph was bounded…

Combinatorics · Mathematics 2018-12-11 Lingjuan Shi , Heping Zhang , Ruizhi Lin

Vertex coloring of a graph $G$ with $n$-colors can be equivalently thought to be a graph homomorphism (edge preserving vertex mapping) of $G$ to the complete graph $K_n$ of order $n$. So, in that sense, the chromatic number $\chi(G)$ of $G$…

Combinatorics · Mathematics 2015-08-27 Julien Bensmail , Christopher Duffy , Sagnik Sen