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Related papers: The zero forcing span of a graph

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For a degree sequence, we define the set of edges that appear in every labeled realization of that sequence as forced, while the edges that appear in none as forbidden. We examine structure of graphs whose degree sequences contain either…

Combinatorics · Mathematics 2019-11-28 Brian Cloteaux

Deduction is a recently introduced graph searching process in which searchers clear the vertex set of a graph with one move each, with each searcher's movement determined by which of its neighbors are protected by other searchers. In this…

Combinatorics · Mathematics 2024-10-31 Andrea Burgess , Danny Dyer , Kerry Ojakian , Lusheng Wang , Mingyu Xiao , Boting Yang

The \emph{zero forcing number}, $Z(G)$, of a graph $G$ is the minimum cardinality of a set $S$ of black vertices (whereas vertices in $V(G)-S$ are colored white) such that $V(G)$ is turned black after finitely many applications of "the…

Combinatorics · Mathematics 2014-12-11 Cong X. Kang , Eunjeong Yi

A set $D$ of vertices in an isolate-free graph $G$ is a semitotal dominating set of $G$ if $D$ is a dominating set of $G$ and every vertex in $D$ is within distance $2$ from another vertex of $D$.The semitotal domination number of $G$ is…

Combinatorics · Mathematics 2021-07-06 Saeid Alikhani , Hassan Zaherifar

We determine upper and lower bounds on the zero forcing number of 2-connected outerplanar graphs in terms of the structure of the weak dual. We show that the upper bound is always at most half the number of vertices of the graph. This work…

Combinatorics · Mathematics 2023-08-23 Nolan Ison , Mark Kempton , Franklin Kenter

Given a graph $G$, one may ask: "What sets of eigenvalues are possible over all weighted adjacency matrices of $G$?" (The weight of an edge is positive or negative, while the diagonal entries can be any real numbers.) This is known as the…

Combinatorics · Mathematics 2021-04-14 Franklin H. j. Kenter , Jephian C. -H. Lin

Let $G=(V,E)$ be a simple graph. A dominating set of $G$ is a subset $S\subseteq V$ such that every vertex not in $S$ is adjacent to at least one vertex in $S$. The cardinality of a smallest dominating set of $G$, denoted by $\gamma(G)$, is…

Combinatorics · Mathematics 2021-01-13 Nima Ghanbari , Saeid Alikhani

A global forcing set for maximal matchings of a graph $G=(V(G), E(G))$ is a set $S \subseteq E(G)$ such that $M_1\cap S \neq M_2 \cap S$ for each pair of maximal matchings $M_1$ and $M_2$ of $G$. The smallest such set is called a minimum…

Combinatorics · Mathematics 2021-07-30 Sandi Klavžar , Mostafa Tavakoli , Gholamreza Abrishami

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

In the literature, several different identification problems in graphs have been studied, the most widely studied such problems are the ones based on dominating sets as a tool of identification. Hereby, the objective is to separate any two…

Combinatorics · Mathematics 2024-12-24 Dipayan Chakraborty , Annegret K. Wagler

For a given positive integer t we consider graphs having maximal independent sets of precisely t distinct cardinalities and restrict our attention to those that have no vertices of degree one. In the situation when t is four or larger and…

Combinatorics · Mathematics 2011-10-20 Bert L. Hartnell , Douglas F. Rall

The notion of forcing sets for perfect matchings was introduced by Harary, Klein, and \v{Z}ivkovi\'{c}. The application of this problem in chemistry, as well as its interesting theoretical aspects, made this subject very active. In this…

Combinatorics · Mathematics 2025-03-04 Javad B. Ebrahimi , Babak Ghanbari

Let $G$ be a simple graph with $2n$ vertices and a perfect matching. We denote by $f(G)$ and $F(G)$ the minimum and maximum forcing number of $G$, respectively. Hetyei obtained that the maximum number of edges of graphs $G$ with a unique…

Combinatorics · Mathematics 2022-11-23 Qianqian Liu , Heping Zhang

Chung, Graham and Wilson defined a set of graphs $\mathcal{H}$ to be forcing, if any sequence of graphs $\{G_n\}_{n \geq 0}$ with $|G_n| = n$ must be quasirandom, whenever $hom(H, G_n)= (p^{|E(H)|}+o(1))n^{|V(H)|}$ for every $H \in…

Combinatorics · Mathematics 2023-12-12 Nikola Spasić

A dominating set of a graph is a subset $D$ of its vertices such that every vertex not in $D$ is adjacent to at least one member of $D$. The domination number of a graph $G$ is the number of vertices in a smallest dominating set of $G$. The…

Combinatorics · Mathematics 2016-03-31 Dieter Mitsche , Xavier Pérez-Giménez , Pawel Prałat

Vertex leaky forcing was recently introduced as a new variation of zero forcing in order to show how vertex leaks can disrupt the zero forcing process in a graph. An edge leak is an edge that is not allowed to be forced across during the…

Combinatorics · Mathematics 2020-09-16 Joseph S. Alameda , Juergen Kritschgau , Michael Young

A dynamic coloring of the vertices of a graph $G$ starts with an initial subset $S$ of colored vertices, with all remaining vertices being non-colored. At each discrete time interval, a colored vertex with exactly one non-colored neighbor…

Combinatorics · Mathematics 2017-02-22 Randy Davila , Michael Henning

Let $G$ be a simple, finite graph with vertex set $V(G)$ and edge set $E(G)$, where each vertex is either colored blue or white. Define the standard zero forcing process on $G$ with the following color-change rule: let $S$ be the set of all…

Combinatorics · Mathematics 2022-02-11 Ma. Nerissa M. Abara , Prince Allan B. Pelayo

Gentner and Rautenbach conjectured that the size of a minimum zero forcing set in a connected graph on $n$ vertices with maximum degree $3$ is at most $\frac{1}{3}n+2$. We disprove this conjecture by constructing a collection of connected…

Combinatorics · Mathematics 2017-12-15 António Girão , Gábor Mészáros , Stephen G. Z. Smith

Let $G=(V,E)$ be a simple connected graph. A perfect matching (or Kekul\'e structure in chemical literature) of $G$ is a set of disjoint edges which covers all vertices of $G$. The anti-forcing number of $G$ is the smallest number of edges…

Combinatorics · Mathematics 2018-07-24 Neda Soltani , Saeid Alikhani