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Related papers: On the complexity of failed zero forcing

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A sequence $D=(d_1,d_2,\ldots,d_n)$ of non-negative integers is called a graphic sequence if there is a simple graph with vertices $v_1,v_2,\ldots,v_n$ such that the degree of $v_i$ is $d_i$ for $1\leq i\leq n$. Given a graph theoretical…

Combinatorics · Mathematics 2025-04-23 Peiyi Duan , Yingzhi Tian

The core vertex set of a graph is an invariant of the graph. It consists of those vertices associated with the non-zero entries of the nullspace vectors of a $\{0,1\}$-adjacency matrix. The remaining vertices of the graph form the…

Combinatorics · Mathematics 2020-05-12 Irene Sciriha , Xandru Mifsud , James Borg

There are typically several nonisomorphic graphs having a given degree sequence, and for any two degree sequence terms it is often possible to find a realization in which the corresponding vertices are adjacent and one in which they are…

Combinatorics · Mathematics 2019-09-17 Michael D. Barrus

One of the most basic results in graph theory states that every graph with at least two vertices has two vertices with the same degree. Since there are graphs without $3$ vertices of the same degree, it is natural to ask if for any fixed…

Combinatorics · Mathematics 2013-12-05 Yair Caro , Asaf Shapira , Raphael Yuster

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

The NP-hard general factor problem asks, given a graph and for each vertex a list of integers, whether the graph has a spanning subgraph where each vertex has a degree that belongs to its assigned list. The problem remains NP-hard even if…

Data Structures and Algorithms · Computer Science 2015-03-19 Gregory Gutin , Eun Jung Kim , Arezou Soleimanfallah , Stefan Szeider , Anders Yeo

A matching is said to be disconnected if the saturated vertices induce a disconnected subgraph and induced if the saturated vertices induce a 1-regular graph. The disconnected and induced matching numbers are defined as the maximum…

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 the graph sharing game, two players share a connected graph $G$ with non-negative weights assigned to the vertices, claiming and collecting the vertices of $G$ one by one, while keeping the set of all claimed vertices connected through…

Combinatorics · Mathematics 2017-04-21 Adam Gągol , Piotr Micek , Bartosz Walczak

If $G(M)$ denotes the subgraph of a graph $G$ induced by the set of vertices that are covered by some matching $M$ in $G$, then $M$ is an induced or a uniquely restricted matching if $G(M)$ is $1$-regular or if $M$ is the unique perfect…

Combinatorics · Mathematics 2018-12-24 Maximilian Fürst

A graph property P is strongly testable if for every fixed \epsilon>0 there is a one-sided \epsilon-tester for P whose query complexity is bounded by a function of \epsilon. In classifying the strongly testable graph properties, the first…

Combinatorics · Mathematics 2011-10-14 Noga Alon , Jacob Fox

A strong geodetic set of a graph~$G=(V,E)$ is a vertex set~$S \subseteq V(G)$ in which it is possible to cover all the remaining vertices of~$V(G) \setminus S$ by assigning a unique shortest path between each vertex pair of~$S$. In the…

Computational Complexity · Computer Science 2022-08-04 Carlos V. G. C. Lima , Vinicius F. dos Santos , João H. G. Sousa , Sebastián A. Urrutia

Zero forcing parameters, associated with graphs, have been studied for over a decade, and have gained popularity as the number of related applications grows. In particular, it is well-known that such parameters are related to certain vertex…

Combinatorics · Mathematics 2015-09-01 Shaun Fallat , Karen Meagher , Abolghasem Soltani , Boting Yang

A graph G is well-covered if all its maximal independent sets are of the same cardinality. Assume that a weight function w is defined on its vertices. Then G is w-well-covered if all maximal independent sets are of the same weight. For…

Discrete Mathematics · Computer Science 2016-11-22 Vadim E. Levit , David Tankus

The cyclability of a graph is the maximum integer $k$ for which every $k$ vertices lie on a cycle. The algorithmic version of the problem, given a graph $G$ and a non-negative integer $k,$ decide whether the cyclability of $G$ is at least…

Combinatorics · Mathematics 2016-01-26 Petr A. Golovach , Marcin Kamiński , Spyridon Maniatis , Dimitrios M. Thilikos

The zero forcing number was introduced as a combinatorial bound on the maximum nullity taken over the set of real symmetric matrices that respect the pattern of an underlying graph. The $Z_q$-forcing game is an analog to the standard zero…

Combinatorics · Mathematics 2023-05-22 Jorge Blanco , Stephanie Einstein , Caleb Hostetler , Jurgen Kritschgau , Daniel Ogbe

The UNIQUE GAMES problem is a central problem in algorithms and complexity theory. Given an instance of UNIQUE GAMES, the STRONG UNIQUE GAMES problem asks to find the largest subset of vertices, such that the UNIQUE GAMES instance induced…

Data Structures and Algorithms · Computer Science 2020-05-19 Suprovat Ghoshal , Anand Louis

We prove that the \emph{standard zero forcing number} $Z(G)$ and the \emph{positive semidefinite zero forcing number} $Z_+(G)$ are equal for all claw-free graphs $G$. This result resolves a conjecture proposed by the computer program…

Combinatorics · Mathematics 2024-12-19 Randy Davila , Houston Schuerger , Ben Small

Motivated by a conjecture from the automated conjecturing program TxGraffiti, in this paper the relationship between the zero forcing number, $Z(G)$, and the vertex independence number, $\alpha(G)$, of cubic and subcubic graphs is explored.…

Combinatorics · Mathematics 2024-11-04 Houston Schuerger , Nathan Warnberg , Michael Young

Zero forcing is an iterative coloring process on a graph that has been widely used in such different areas as the modelling of propagation phenomena in networks and the study of minimum rank problems in matrices and graphs. This paper deals…

Combinatorics · Mathematics 2021-09-24 Josep Fàbrega , Jaume Martí-Farré , Xavier Muñoz