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Related papers: Maximum nullity and zero forcing of circulant grap…

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Given a graph $G$ and a real number $0\le p\le 1$, we define the random set $B_p(G)\subset V(G)$ by including each vertex independently and with probability $p$. We investigate the probability that the random set $B_p(G)$ is a zero forcing…

Combinatorics · Mathematics 2022-08-30 Bryan Curtis , Luyining Gan , Jamie Haddock , Rachel Lawrence , Sam Spiro

Zero forcing is a combinatorial game played on a graph with the ultimate goal of changing the colour of all the vertices at minimal cost. Originally this game was conceived as a one player game, but later a two-player version was devised…

The forcing number of a graph with a perfect matching $M$ is the minimum number of edges in $M$ whose endpoints need to be deleted, such that the remaining graph only has a single perfect matching. This number is of great interest in…

Discrete Mathematics · Computer Science 2024-02-01 Maximilian Gorsky , Fabian Kreßin

Zero forcing is a deterministic iterative graph colouring process in which vertices are coloured either blue or white, and in every round, any blue vertices that have a single white neighbour force these white vertices to become blue. Here…

Combinatorics · Mathematics 2021-03-17 Natalie C. Behague , Trent Marbach , Pawel Pralat

Zero forcing in a graph refers to the evolution of vertex states under repeated application of a color change rule. Typically the states are chosen to be blue and white, and a forcing set is an initial set of blue vertices such that all of…

Combinatorics · Mathematics 2025-11-21 Daniela Ferrero , H. Tracy Hall , Leslie Hogben , Mark Hunnell , Ben Small

This article studies the \emph{$k$-forcing number} for oriented graphs, generalizing both the \emph{zero forcing number} for directed graphs and the $k$-forcing number for simple graphs. In particular, given a simple graph $G$, we introduce…

Combinatorics · Mathematics 2017-09-12 Yair Caro , Randy Davila , Ryan Pepper

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

Zero forcing is an iterative process on a graph used to bound the maximum nullity. The process begins with select vertices as colored, and the remaining vertices can become colored under a specific color change rule. The goal is to find a…

Combinatorics · Mathematics 2017-09-27 Franklin H. J. Kenter , Jephian C. -H. Lin

The minimum rank problem is to determine for a graph $G$ the smallest rank of a Hermitian (or real symmetric) matrix whose off-diagonal zero-nonzero pattern is that of the adjacency matrix of $G$. Here $G$ is taken to be a circulant graph,…

Combinatorics · Mathematics 2015-11-26 Louis Deaett , Seth A. Meyer

Sidorenko's conjecture states that the number of copies of any given bipartite graph in another graph of given density is asymptotically minimized by a random graph. The forcing conjecture further strengthens this, claiming that any…

Combinatorics · Mathematics 2024-12-18 Aldo Kiem , Olaf Parczyk , Christoph Spiegel

Zero forcing is a process that colors the vertices of a graph blue by starting with some vertices blue and applying a color change rule. Throttling minimizes the sum of the number of initial blue vertices and the time to color the graph. In…

Combinatorics · Mathematics 2019-09-17 Emelie Curl , Jesse Geneson , Leslie Hogben

This paper begins the study of reconfiguration of zero forcing sets, and more specifically, the zero forcing graph. Given a base graph $G$, its zero forcing graph, $\mathscr{Z}(G)$, is the graph whose vertices are the minimum zero forcing…

Combinatorics · Mathematics 2020-09-02 Jesse Geneson , Ruth Haas , Leslie Hogben

The rank of a graph is defined to be the rank of its adjacency matrix. A graph is called reduced if it has no isolated vertices and no two vertices with the same set of neighbors. We determine the maximum order of reduced triangle-free…

Combinatorics · Mathematics 2014-04-15 E. Ghorbani , A. Mohammadian , B. Tayfeh-Rezaie

A zero forcing set is a set $S$ of vertices of a graph $G$, called forced vertices of $G$, which are able to force the entire graph by applying the following process iteratively: At any particular instance of time, if any forced vertex has…

Combinatorics · Mathematics 2023-06-22 Jessy Sujana G. , T. M. Rajalaxmi , Indra Rajasingh , R. Sundara Rajan

While there have been many results on lower bounds for Max Cut in unweighted graphs, there are only few results for lower bounds for Max Cut in weighted graphs. In this paper, we launch an extensive study of lower bounds for Max Cut in…

Combinatorics · Mathematics 2024-08-13 Gregory Gutin , Anders Yeo

Let $G$ be a simple graph with $2n$ vertices and a perfect matching. The forcing number $f(G,M)$ of a perfect matching $M$ of $G$ is the smallest cardinality of a subset of $M$ that is contained in no other perfect matching of $G$. Among…

Combinatorics · Mathematics 2022-11-23 Qian qian Liu , He ping Zhang

A connected forcing set of a graph is a zero forcing set that induces a connected subgraph. In this paper, we introduce and study CF-dense graphs -- graphs in which every vertex belongs to some minimum connected forcing set. We identify…

Combinatorics · Mathematics 2025-07-16 Boris Brimkov , Randy Davila , Houston Schuerger

Zero forcing is a graph coloring process that is used to model spreading phenomena in real-world scenarios. It can also be viewed as a single-player combinatorial game on a graph, where the player's goal is to select a subset of vertices of…

Combinatorics · Mathematics 2025-09-05 Aida Abiad , Maryam Moghaddas

We consider bounds on maximum nullity of a graph via transversal numbers of compatible collections of forts. Results include generalizations of theorems from symmetric to combinatorially symmetric matrices, special bases of matrix…

Combinatorics · Mathematics 2024-07-08 Veronika Furst , John Hutchens , Lon Mitchell , Yaqi Zhang

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
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