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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

The fractional list packing number $\chi_{\ell}^{\bullet}(G)$ of a graph $G$ is a graph invariant that has recently arisen from the study of disjoint list-colourings. It measures how large the lists of a list-assignment $L:V(G)\rightarrow…

Combinatorics · Mathematics 2026-04-13 Stijn Cambie , Wouter Cames van Batenburg

We introduce a new variant of zero forcing - signed zero forcing. The classical zero forcing number provides an upper bound on the maximum nullity of a matrix with a given graph (i.e. zero-nonzero pattern). Our new variant provides an…

Combinatorics · Mathematics 2013-07-09 Felix Goldberg , Abraham Berman

Recently, Dvo\v{r}\'ak, Norin, and Postle introduced flexibility as an extension of list coloring on graphs [JGT 19']. In this new setting, each vertex $v$ in some subset of $V(G)$ has a request for a certain color $r(v)$ in its list of…

Combinatorics · Mathematics 2023-06-13 Bernard Lidický , Tomáš Masařík , Kyle Murphy , Shira Zerbib

A dynamic coloring of the vertices of a graph $G$ starts with an initial subset $F$ of colored vertices, with all remaining vertices being non-colored. At each time step, a colored vertex with exactly one non-colored neighbor forces this…

Combinatorics · Mathematics 2019-03-21 Meysam Alishahi , Elahe Rezaei-Sani , Elahe Sharifi

The burning and forcing processes are both instances of propagation processes on graphs that are commonly used to model real-world spreading phenomena. The contribution of this paper is two-fold. We first establish a connection between…

Combinatorics · Mathematics 2026-02-16 Aida Abiad , Pax Mallee

We define a method for edge coloring signed graphs and what it means for such a coloring to be proper. Our method has many desirable properties: it specializes to the usual notion of edge coloring when the signed graph is all-negative, it…

Combinatorics · Mathematics 2018-12-05 Richard Behr

A conjecture of Alon, Krivelevich, and Sudakov states that, for any graph $F$, there is a constant $c_F > 0$ such that if $G$ is an $F$-free graph of maximum degree $\Delta$, then $\chi(G) \leq c_F \Delta / \log\Delta$. Alon, Krivelevich,…

Combinatorics · Mathematics 2022-01-25 James Anderson , Anton Bernshteyn , Abhishek Dhawan

Independently posed by Behzad and Vizing, the Total Coloring Conjecture asserts that the total chromatic number of a simple connected graph $G$ is either $\Delta(G)+1$ or $\Delta(G)+2$, where $\Delta(G)$ is the largest degree of any vertex…

Combinatorics · Mathematics 2026-05-13 I. J. Dejter

Probabilistic zero-forcing is a coloring process on a graph. In this process, an initial set of vertices is colored blue, and the remaining vertices are colored white. At each time step, blue vertices have a non-zero probability of forcing…

Combinatorics · Mathematics 2020-10-26 David Hu , Alec Sun

A dynamic coloring of the vertices of a graph $G$ 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 exactly one non-colored neighbor…

Combinatorics · Mathematics 2018-01-17 Randy Davila , Michael Henning

The global forcing number of a graph G is the minimal cardinality of an edge subset discriminating all perfect matchings of G, denoted by gf(G). For any perfect matching M of G, the minimal cardinality of an edge subset S in E(G)-M such…

Combinatorics · Mathematics 2022-11-08 Yaxian Zhang , Heping Zhang

Zero forcing can be described as a combinatorial game on a graph that uses a color change rule in which vertices change white vertices to blue. The throttling number of a graph minimizes the sum of the number of vertices initially colored…

Combinatorics · Mathematics 2021-02-23 Joshua Carlson , Juergen Kritschgau

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

Graph coloring problems are a central topic of study in the theory of algorithms. We study the problem of partially coloring partially colorable graphs. For $\alpha \leq 1$ and $k \in \mathbb{Z}^+$, we say that a graph $G=(V,E)$ is…

Data Structures and Algorithms · Computer Science 2019-09-02 Suprovat Ghoshal , Anand Louis , Rahul Raychaudhury

Given a graph $G$, the zero forcing number of $G$, $Z(G)$, is the smallest cardinality of any set $S$ of vertices on which repeated applications of the forcing rule results in all vertices being in $S$. The forcing rule is: if a vertex $v$…

Combinatorics · Mathematics 2022-09-21 Aidan Johnson , Andrew E. Vick , Darren A. Narayan

While a number of bounds are known on the zero forcing number $Z(G)$ of a graph $G$ expressed in terms of the order of a graph and maximum or minimum degree, we present two bounds that are related to the (upper) total domination number…

Combinatorics · Mathematics 2023-10-12 Boštjan Brešar , María Gracia Cornet , Tanja Dravec , Michael Henning

We introduce a family of forcing notions that are helpful in showing that certain graphs do not have countable colourings of (additive) Borel class alpha. We construct graphs that are ''weakly minimal'' for such colourings.

General Topology · Mathematics 2026-04-08 Noam Greenberg , Dominique Lecomte , Dan Turetsky , Miroslav Zelen

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

L. Soukup formulated an abstract framework in his introductory paper for proving theorems about uncountable graphs by subdividing them by an increasing continuous chain of elementary submodels. The applicability of this method relies on the…

Combinatorics · Mathematics 2023-07-13 Attila Joó