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Related papers: Zero forcing and maximum nullity for hypergraphs

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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

A dominating set $D_{f}\subseteq V(G)$ of vertices in a graph $G$ is called a \emph{dom-forcing set} if the sub-graph induced by $\langle D_{f} \rangle$ must form a zero forcing set. The minimum cardinality of such a set is known as the…

Combinatorics · Mathematics 2024-11-04 Susanth P , Charles Dominic , Premodkumar K P

We investigate the zero-forcing number for triangle-free graphs. We improve upon the trivial bound, $\delta \le Z(G)$ where $\delta$ is the minimum degree, in the triangle-free case. In particular, we show that $2 \delta - 2 \le Z(G)$ for…

Combinatorics · Mathematics 2014-06-13 Randy Davila , Franklin Kenter

In this paper, an upper bound on the nullity of signed graphs in terms of the cyclomatic number and the number of pendant vertices is proved, and the corresponding extremal signed graphs are completely characterized.

Combinatorics · Mathematics 2022-08-16 Keming Liu , Xiying Yuan

This paper proves a conjecture generated by the artificial intelligence conjecturing program called \emph{TxGraffiti}. More specifically, we show that if $G$ is a connected, cubic, and claw-free graph, then $Z(G) \le \gamma(G) + 2$, where…

Combinatorics · Mathematics 2024-11-20 Randy R. Davila

In this paper we begin the study of well-failed graphs, that is, graphs in which every maximal failed zero forcing set is a maximum failed zero forcing set, or equivalently, in which every minimal fort is a minimum fort. We characterize…

Combinatorics · Mathematics 2025-02-03 Bonnie Jacob

This study delves into the incidence matrices of hypergraphs, with a focus on two types: the edge-vertex incidence matrix and the vertex-edge incidence matrix. The edge-vertex incidence matrix is a matrix in which the rows represent…

Combinatorics · Mathematics 2025-10-10 Samiron Parui

For a simple graph, the minimum rank problem is to determine the smallest rank among the symmetric matrices whose off-diagonal nonzero entries occur in positions corresponding to the edges of the graph. Bounds on this minimum rank (and on…

Combinatorics · Mathematics 2025-11-03 Louis Deaett , Derek Young

Let $G$ be a graph that admits a perfect matching. A {\sf forcing set} for a perfect matching $M$ of $G$ is a subset $S$ of $M$, such that $S$ is contained in no other perfect matching of $G$. This notion originally arose in chemistry in…

Combinatorics · Mathematics 2009-03-17 Peyman Afshani , Hamed Hatami , Ebadollah S. Mahmoodian

The zero forcing number of a graph $G$, denoted by $Z(G)$, is the minimum cardinality of a set $S$ of black vertices (where vertices in $V(G)\setminus S$ are colored white) such that $V(G)$ is turned black after finitely many applications…

Combinatorics · Mathematics 2017-02-20 I. Javaid , I. Irshad , M. Batool , Z. Raza

The k-forcing number of a graph is a generalization of the zero forcing number. In this note, we give a greedy algorithm to approximate the k-forcing number of a graph. Using this dynamic approach, we give corollaries which improve upon two…

Combinatorics · Mathematics 2014-05-30 Yair Caro , Ryan Pepper

Irredundance has been studied in the context of dominating sets, via the concept of private neighbor. Here irredundance of zero forcing sets is introduced via the concept of a private fort and the upper and lower zero forcing irrdedundance…

Combinatorics · Mathematics 2026-03-31 Bryan A. Curtis , Leslie Hogben , Adriana Roux

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

Let ${\mathcal G}$ be an infinite family of connected graphs and let $k$ be a positive integer. We say that $k$ is ${\it forcing}$ for ${\mathcal G}$ if for all $G \in {\mathcal G}$ but finitely many, the following holds. Any…

Combinatorics · Mathematics 2017-11-28 Yair Caro , Raphael Yuster

Probabilistic zero forcing is a graph coloring process in which blue vertices "infect" (color blue) white vertices with a probability proportional to the number of neighboring blue vertices. We introduce reversion probabilistic zero forcing…

Combinatorics · Mathematics 2024-04-24 Zachary Brennan

We define direct sums and a corresponding notion of connectedness for graph limits. Every graph limit has a unique decomposition as a direct sum of connected components. As is well-known, graph limits may be represented by symmetric…

Combinatorics · Mathematics 2008-04-10 Svante Janson

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 (simple) hypergraph is a family H of pairwise incomparable sets of a finite set. We say that a hypergraph H is a domination hypergraph if there is at least a graph G such that the collection of minimal dominating sets of G is equal to H.…

Combinatorics · Mathematics 2016-05-06 Jaume Martí-Farré , Mercè Mora , José Luis Ruiz

Power domination in graphs arises from the problem of monitoring an electric power system by placing as few measurement devices in the system as possible. A power dominating set of a graph is a set of vertices that observes every vertex in…

Combinatorics · Mathematics 2017-11-15 Chassidy Bozeman , Boris Brimkov , Craig Erickson , Daniela Ferrero , Mary Flagg , Leslie Hogben

Let $G$ be a simple graph with a perfect matching. Deng and Zhang showed that the maximum anti-forcing number of $G$ is no more than the cyclomatic number. In this paper, we get a novel upper bound on the maximum anti-forcing number of $G$…

Combinatorics · Mathematics 2023-06-22 Lingjuan Shi , Heping Zhang