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Let $G=(V,E)$ be a finite undirected graph. A set $S$ of vertices in $V$ is said to be total $k$-dominating if every vertex in $V$ is adjacent to at least $k$ vertices in $S$. The total $k$-domination number, $\gamma_{kt}(G)$, is the…

Combinatorics · Mathematics 2022-05-11 Walter Carballosa , Justin Wisby

A vertex set $D$ of a graph $G$ is said to be a dominating set if every vertex of $V(G)\setminus D$ is adjacent to at least a vertex in $D$, and the domination number $\gamma(G)$ ($\gamma$, for short) is the minimum cardinality of all…

Combinatorics · Mathematics 2013-10-18 Guanglong Yu , Shu-Guang Guo , Rong Zhang , Yarong Wu

A set S of vertices in a graph G is a dominating set of G if every vertex not in S is adjacent to a vertex in S . The domination number of G, denoted by $\gamma$(G), is the minimum cardinality of a dominating set in G. In a breakthrough…

Discrete Mathematics · Computer Science 2024-10-07 Paul Dorbec , Michael Antony Henning

Let $G=(V,E)$ be a simple graph. A dominating set of $G$ is a subset $D\subseteq V$ such that every vertex not in $D$ is adjacent to at least one vertex in $D$. The cardinality of a smallest dominating set of $G$, denoted by $\gamma(G)$, is…

Combinatorics · Mathematics 2024-01-17 Nima Ghanbari , Saeid Alikhani , Mohammad Ali Dehghanizadeh

The power domination problem focuses on finding the optimal placement of phase measurement units (PMUs) to monitor an electrical power network. In the context of graphs, the power domination number of a graph $G$, denoted $\gamma_P(G)$, is…

Combinatorics · Mathematics 2022-09-09 Sarah E. Anderson , Kirsti Kuenzel

A \emph{perfect Roman dominating function} (PRDF) on a graph $G = (V, E)$ is a function $f : V \rightarrow \{0, 1, 2\}$ satisfying the condition that every vertex $u$ for which $f(u) = 0$ is adjacent to exactly one vertex $v$ for which…

Combinatorics · Mathematics 2018-06-11 Zepeng Li , Zehui Shao , Yongsheng Rao , Pu Wu , Shaohui Wang

Let $G$ be a connected graph. A non-empty $T\subseteq V(G)$ is a $2$-\textit{movable total dominating set} of $G$ if $T$ is a total dominating set and for every pair $x,y \in T$, $T \backslash \{x, y\}$ is a total dominating set in $G$, or…

Combinatorics · Mathematics 2025-08-18 Ariel C. Pedrano , Rolando N. Paluga

A subset $S$ of vertices of $G$ is a \textit{dominating set} of $G$ if every vertex in $V(G)-S$ has a neighbor in $S$. The \textit{domination number} \(\gamma(G)\) is the minimum cardinality of a dominating set of $G$. A dominating set $S$…

Combinatorics · Mathematics 2025-09-26 Yuhan Ma

A set $D \subseteq V(G)$ is a \emph{total dominating set} of $G$ if for every vertex $v \in V(G)$ there exists a vertex $u \in D$ such that $u$ and $v$ are adjacent. A total dominating set of $G$ of minimum cardinality is called a…

Combinatorics · Mathematics 2015-02-19 Cong X. Kang

Addressing a problem posed by Chellali, Haynes, and Hedetniemi (Discrete Appl. Math. 178 (2014) 27-32) we prove $\gamma_{r2}(G)\leq 2\gamma_r(G)$ for every graph $G$, where $\gamma_{r2}(G)$ and $\gamma_r(G)$ denote the $2$-rainbow…

Combinatorics · Mathematics 2015-07-20 Jose D. Alvarado , Simone Dantas , Dieter Rautenbach

Let $\gamma_g(G)$ be the game domination number of a graph $G$. It is proved that if ${\rm diam}(G) = 2$, then $\gamma_g(G) \le \left\lceil \frac{n(G)}{2} \right\rceil- \left\lfloor \frac{n(G)}{11}\right\rfloor$. The bound is attained: if…

Combinatorics · Mathematics 2021-02-03 Csilla Bujtás , Vesna Iršič , Sandi Klavžar , Kexiang Xu

For a graph $G = (V(G), E(G))$, a dominating set $D$ is a vertex subset of $V(G)$ in which every vertex of $V(G) \setminus D$ is adjacent to a vertex in $D$. The domination number of $G$ is the minimum cardinality of a dominating set of $G$…

Combinatorics · Mathematics 2022-08-16 David A. Kalarkop , Pawaton Kaemawichanurat , Raghavachar Rangarajan

In the domination game, introduced by Bre\v{s}ar, Klav\v{z}ar and Rall in 2010, Dominator and Staller alternately select a vertex of a graph $G$. A move is legal if the selected vertex $v$ dominates at least one new vertex -- that is, if we…

Combinatorics · Mathematics 2014-07-01 Csilla Bujtás

A set $D$ of vertices in a graph $G$ is called dominating if every vertex of $G$ is either in $D$ or adjacent to a vertex of $D$. The paired domination number $\gamma_{\mathrm{pr}}(G)$ of $G$ is the minimum size of a dominating set whose…

Combinatorics · Mathematics 2020-08-11 Amanda Burcroff

Let $G=(V,E)$ be a simple connected graph. A set of vertices $S\subseteq V$ is said to be a dominating set if for any vertex in $V\setminus S$ is adjacent to at least one vertex in $S$. The domination number $\gamma(G)$ of $G$ is the…

Combinatorics · Mathematics 2016-03-25 Lang Tang , Shenglin Zhou

Let $\gamma_g(G)$ and $\gamma_{tg}(G)$ be the game domination number and the total game domination number of a graph $G$, respectively. Then $G$ is $\gamma_g$-perfect (resp. $\gamma_{tg}$-perfect), if every induced subgraph $F$ of $G$…

Combinatorics · Mathematics 2019-08-27 Csilla Bujtás , Vesna Iršič , Sandi Klavžar

We prove that for every graph $G$ on $n$ vertices and with minimum degree five, the domination number $\gamma(G)$ cannot exceed $n/3$. The proof combines an algorithmic approach and the discharging method. Using the same technique, we…

Combinatorics · Mathematics 2020-05-18 Csilla Bujtás

A signed dominating function of graph $\Gamma$ is a function $g :V(\Gamma) \longrightarrow \{-1,1\}$ such that $\sum_{u \in N[v]}g(u) >0$ for each $v \in V(\Gamma)$. The signed domination number $\gamma_{_S}(\Gamma)$ is the minimum weight…

Combinatorics · Mathematics 2019-10-10 Saeid Alikhani , Fatemeh Ramezani , Ebrahim Vatandoost

Let $G=(V,E)$ be a simple graph. A dominating set of $G$ is a subset $D\subseteq V$ such that every vertex not in $D$ is adjacent to at least one vertex in $D$. The cardinality of a smallest dominating set of $G$, denoted by $\gamma(G)$, is…

Combinatorics · Mathematics 2022-01-20 Nima Ghanbari

Given a function $f\colon V(G) \to \mathbb{Z}_{\geq 0}$ on a graph $G$, $AN(v)$ denotes the set of neighbors of $v \in V(G)$ that have positive labels under $f$. In 2021, Ahangar et al.~introduced the notion of $[k]$-Roman Dominating…

Combinatorics · Mathematics 2024-06-18 Atílio Gomes Luiz , Francisco Anderson Silva Vieira