English
Related papers

Related papers: Forcing Brushes

200 papers

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

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

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

Given a graph $G=(V,E)$ and a set of vertices marked as filled, we consider a color-change rule known as zero forcing. A set $S$ is a zero forcing set if filling $S$ and applying all possible instances of the color change rule causes all…

Combinatorics · Mathematics 2023-08-16 Eric Ufferman , Nicolas Swanson

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

We study pairs of graphs (H_1,H_2) such that every graph with the densities of H_1 and H_2 close to the densities of H_1 and H_2 in a random graph is quasirandom; such pairs (H_1,H_2) are called forcing. Non-bipartite forcing pairs were…

Combinatorics · Mathematics 2019-06-11 Tamas Hubai , Dan Kral , Olaf Parczyk , Yury Person

In this paper, we showcase the process of using an automated conjecturing program called \emph{TxGraffiti} written and maintained by the second author. We begin by proving a conjecture formulated by \emph{TxGraffiti} that for a claw-free…

Combinatorics · Mathematics 2022-09-13 Boris Brimkov , Randy Davila , Houston Schuerger , Michael Young

An equivalence graph is a disjoint union of cliques, and the equivalence number $\mathit{eq}(G)$ of a graph $G$ is the minimum number of equivalence subgraphs needed to cover the edges of $G$. We consider the equivalence number of a line…

Combinatorics · Mathematics 2011-02-16 L. Esperet , J. Gimbel , A. King

We define the cover number of a graph $G$ by a graph class $\mathcal P$ as the minimum number of graphs of class $\mathcal P$ required to cover the edge set of $G$. Taking inspiration from a paper by Harary, Hsu and Miller, we find an exact…

Combinatorics · Mathematics 2025-02-24 Márton Marits

A leak is a vertex that is not allowed to perform a force during the zero forcing process. Leaky forcing was recently introduced as a new variation of zero forcing in order to analyze how leaks in a network disrupt the zero forcing process.…

Combinatorics · Mathematics 2020-08-18 Joseph S. Alameda , Jürgen Kritschgau , Nathan Warnberg , Michael Young

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

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

The concept of the brush number $b_r(G)$ was introduced for a simple connected undirected graph $G$. The concept will be applied to the Mycielskian graph $\mu(G)$ of a simple connected graph $G$ to find $b_r(\mu(G))$ in terms of an…

Combinatorics · Mathematics 2015-01-16 Johan Kok , Susanth C , Sunny Joseph Kalayathankal

Zero forcing and power domination are iterative processes on graphs where an initial set of vertices are observed, and additional vertices become observed based on some rules. In both cases, the goal is to eventually observe the entire…

Combinatorics · Mathematics 2017-03-02 Daniela Ferrero , Leslie Hogben , Franklin H. J. Kenter , Michael Young

Let $G$ be a simple graph whose vertices are partitioned into two subsets, called filled vertices and empty vertices. A vertex $v$ is said to be forced by a filled vertex $u$ if $v$ is a unique empty neighbor of $u$. If we can fill all the…

Combinatorics · Mathematics 2016-09-02 Yaroslav Shitov

Let $S$ be a set of vertices of a graph $G$. Let $cl(S)$ be the set of vertices built from $S$, by iteratively applying the following propagation rule: if a vertex and all but exactly one of its neighbors are in $cl(S)$, then the remaining…

Combinatorics · Mathematics 2019-08-09 Najibeh Shahbaznejad , Ignacio M. Pelayo , Adel P. Kazemi

The forcing number of a perfect matching $M$ in a graph $G$ is the smallest number of edges inside $M$ that can not be contained in other perfect matchings. The anti-forcing number of $M$ is the smallest number of edges outside $M$ whose…

Combinatorics · Mathematics 2020-12-25 Kai Deng , Huazhong Lü , Tingzeng Wu

Let $G$ be a simple and finite graph without isolated vertices. In this paper we study forcing sets (zero forcing sets) which induce a subgraph of $G$ without isolated vertices. Such a set is called a total forcing set, introduced and first…

Combinatorics · Mathematics 2017-02-28 Randy Davila , Michael A. Henning

We define the anti-forcing number of a perfect matching $M$ of a graph $G$ as the minimal number of edges of $G$ whose deletion results in a subgraph with a unique perfect matching $M$, denoted by $af(G,M)$. The anti-forcing number of a…

Combinatorics · Mathematics 2014-06-17 Hongchuan Lei , Yeong-Nan Yeh , Heping Zhang

A connected graph G is matching covered if every edge lies in some perfect matching of G. Lovasz proved that every matching covered graph G can be uniquely decomposed into a list of bricks (nonbipartite) and braces (bipartite) up to…

Combinatorics · Mathematics 2024-11-27 Yaxian Zhang , Fuliang Lu , Heping Zhang