English
Related papers

Related papers: Zero Forcing and Vertex Independence Number on Cub…

200 papers

The prime-coprime graph $\Theta(G)$ of a finite group $G$ is the simple graph with vertex set $G$, where two distinct elements are adjacent whenever the greatest common divisor of their orders is either $1$ or a prime. We characterize all…

Group Theory · Mathematics 2026-04-21 Ravi Ranjan , Shubh Narayan Singh , Surbhi Kumari , Shidra Jamil

A well known upper bound for the independence number $\alpha(G)$ of a graph $G$, due to Cvetkovi\'{c}, is that \begin{equation*} \alpha(G) \le n^0 + \min\{n^+ , n^-\} \end{equation*} where $(n^+, n^0, n^-)$ is the inertia of $G$. We prove…

Combinatorics · Mathematics 2021-10-05 Pawel Wocjan , Clive Elphick , Aida Abiad

Zero forcing is an iterative graph coloring process where at each discrete time step, a colored vertex with a single uncolored neighbor forces that neighbor to become colored. The zero forcing number of a graph is the cardinality of the…

Discrete Mathematics · Computer Science 2017-02-06 Boris Brimkov , Caleb C. Fast , Illya V. Hicks

A set $S$ of vertices of a graph $G$ is exponentially independent if, for every vertex $u$ in $S$, $$\sum\limits_{v\in S\setminus \{ u\}}\left(\frac{1}{2}\right)^{{\rm dist}_{(G,S)}(u,v)-1}<1,$$ where ${\rm dist}_{(G,S)}(u,v)$ is the…

Combinatorics · Mathematics 2020-10-05 Stéphane Bessy , Johannes Pardey , Dieter Rautenbach

For a graph $G$ in which vertices are either black or white, a zero forcing process is an iterative vertex color changing process such that the only white neighbor of a black vertex becomes black in the next time step. A zero forcing set is…

Combinatorics · Mathematics 2025-08-26 Hau-Yi Lin , Wu-Hsiung Lin , Gerard Jennhwa Chang

It is known that the zero forcing number of a graph is an upper bound for the maximum nullity of the graph. In this paper, we search for characteristics of a graph that guarantee the maximum nullity of the graph and the zero forcing number…

Combinatorics · Mathematics 2019-12-17 Derek Young

Let ${\rm Z}(G)$ and ${\rm gp}(G)$ be the zero forcing number and the general position number of a graph $G$, respectively. Known results imply that ${\rm gp}(T)\ge {\rm Z}(T) + 1$ holds for every nontrivial tree $T$. It is proved that the…

Combinatorics · Mathematics 2021-12-21 Hongbo Hua , Xinying Hua , Sandi Klavžar

Zero forcing is an iterative graph coloring process, where given a set of initially colored vertices, a colored vertex with a single uncolored neighbor causes that neighbor to become colored. A zero forcing set is a set of initially colored…

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

An independent set in a graph $G$ is a set of pairwise non-adjacent vertices. A tree decomposition of $G$ is a pair $(T, \chi)$ where $T$ is a tree and $\chi : V(T) \rightarrow 2^{V(G)}$ is a function satisfying the following two axioms:…

Combinatorics · Mathematics 2026-05-07 Maria Chudnovsky , Ajaykrishnan E S , Daniel Lokshtanov

The zero forcing number is the minimum number of black vertices that can turn a white graph black following a single neighbour colour forcing rule. The zero forcing number provides topological information about linear algebra on graphs,…

Combinatorics · Mathematics 2021-02-10 Alexei Vazquez

For a graph $G$, its $k$-th power $G^k$ is constructed by placing an edge between two vertices if they are within distance $k$ of each other. The $k$-independence number $\alpha_k(G)$ is defined as the independence number of $G^k$. By using…

Combinatorics · Mathematics 2024-11-15 Aida Abiad , Jiang Zhou

Let $G$ be a graph with vertex set $V(G)$ and edge set $E(G)$. A set $I_0(G) \subseteq V(G)$ is a vertex independent set if no two vertices in $I_0(G)$ are adjacent in $G$. We study $\alpha_1(G)$, which is the maximum cardinality of a set…

Combinatorics · Mathematics 2024-06-25 Zekhaya B. Shozi

In this note, we study a dynamic vertex coloring for a graph $G$. In particular, one starts with a certain set of vertices black, and all other vertices white. Then, at each time step, a black vertex with exactly one white neighbor forces…

Combinatorics · Mathematics 2018-11-02 Randy Davila , Thomas Kalinowski , Sudeep Stephen

For a graph $G$, a vertex subset $S$ is called a maximum generalized $k$-independent set if the induced subgraph $G[S]$ does not contain a $k$-tree as its subgraph, and the subset has maximum cardinality. The generalized $k$-independence…

Combinatorics · Mathematics 2025-09-15 Jing Huang

Zero forcing number has recently become an interesting graph parameter studied in its own right since its introduction by the "AIM Minimum Rank -- Special Graphs Work Group", whereas metric dimension is a well-known graph parameter. We…

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

In this paper, we study minimal (with respect to inclusion) zero forcing sets. We first investigate when a graph can have polynomially or exponentially many distinct minimal zero forcing sets. We also study the maximum size of a minimal…

Combinatorics · Mathematics 2022-04-18 Boris Brimkov , Joshua Carlson

In this paper, we study a dynamic coloring of the vertices of a graph $G$ that 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…

Combinatorics · Mathematics 2016-10-27 Randy Davila , Michael Henning

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

We define a new integer invariant of a finite graph G, the freeness index, that measures the extent to which G can be embedded in the 3-sphere so that it and its subgraphs have ``simple" complements, i.e., complements which are homeomorphic…

Combinatorics · Mathematics 2022-06-28 Abigail Thompson