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Related papers: Domination and fractional domination in digraphs

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This paper initiates the study of fractional eternal domination in graphs, a natural relaxation of the well-studied eternal domination problem. We study the connections to flows and linear programming in order to obtain results on the…

Combinatorics · Mathematics 2023-04-25 Fnu Devvrit , Aaron Krim-Yee , Nithish Kumar , Gary MacGillivray , Ben Seamone , Virgélot Virgile , AnQi Xu

A set of vertices of a graph $G$ such that each vertex of $G$ is either in the set or is adjacent to a vertex in the set is called a dominating set of $G$. If additionally, the set of vertices induces a connected subgraph of $G$ then the…

Combinatorics · Mathematics 2024-03-04 Felicity Bryant , Elena Pavelescu

A graph $G$ is a \emph{cover} of a graph $F$ if there exists an onto mapping $\pi : V(G) \to V(F)$, called a (\emph{covering}) \emph{projection}, such that $\pi$ maps the neighbours of any vertex $v$ in $G$ bijectively onto the neighbours…

Combinatorics · Mathematics 2025-11-26 Dickson Y. B. Annor

A set $D$ of vertices in an isolate-free graph $G$ is a semitotal dominating set of $G$ if $D$ is a dominating set of $G$ and every vertex in $D$ is within distance $2$ from another vertex of $D$.The semitotal domination number of $G$ is…

Combinatorics · Mathematics 2021-07-06 Saeid Alikhani , Hassan Zaherifar

Let $G$ be a graph with no isolated vertex. In this paper, we study a parameter that is a relaxation of arguably the most important domination parameter, namely the total domination number, $\gamma_t(G)$. A set $S$ of vertices in $G$ is a…

Combinatorics · Mathematics 2014-10-02 Michael A. Henning , Viroshan Naicker

An edge dominating set $F$ of a graph $G=(V,E)$ is an \textit{edge cut dominating set} if the subgraph $\langle V,G-F \rangle$ is disconnected. The \textit{edge cut domination number} $\gamma_{ct}(G)$ of $G$ is the minimum cardinality of an…

Combinatorics · Mathematics 2016-05-17 Todd Fenstermacher , Stephen Hedetniemi , Renu Laskar

The domatic number of a graph is the maximum number of vertex disjoint dominating sets that partition the vertex set of the graph. In this paper we consider the fractional variant of this notion. Graphs with fractional domatic number 1 are…

Combinatorics · Mathematics 2023-10-17 Maximilien Gadouleau , Nathaniel Harms , George B. Mertzios , Viktor Zamaraev

The independent domination number of a finite graph G is the minimum cardinality of an independent dominating set of vertices. The independent bondage number of G is the minimum cardinality of a set of edges whose deletion results in a…

Combinatorics · Mathematics 2024-02-06 E. G. K. M. Gamlath , Bing Wei , Talmage James Reid

A numbering $f$ of a graph $G$ of order $n$ is a labeling that assigns distinct elements of the set $\left\{ 1,2,\ldots ,n\right\} $ to the vertices of $G$. The strength $\textrm{str}_{f}\left( G\right)$ of a numbering $f:V\left( G\right)…

Combinatorics · Mathematics 2023-04-04 Yukio Takahashi , Rikio Ichishima , Francesc A. Muntaner-Batle

The orientable domination number, ${\rm DOM}(G)$, of a graph $G$ is the largest domination number over all orientations of $G$. In this paper, ${\rm DOM}$ is studied on different product graphs and related graph operations. The orientable…

Combinatorics · Mathematics 2022-11-07 Sarah Anderson , Boštjan Brešar , Sandi Klavžar , Kirsti Kuenzel , Douglas F. Rall

For a graph $G$, the $\gamma$-graph of $G$, $G(\gamma)$, is the graph whose vertices correspond to the minimum dominating sets of $G$, and where two vertices of $G(\gamma)$ are adjacent if and only if their corresponding dominating sets in…

Combinatorics · Mathematics 2017-07-10 C. M. Mynhardt , L. E. Teshima

A directed dominating set in a directed graph $D$ is a set $S$ of vertices of $V$ such that every vertex $u \in V(D) \setminus S$ has an adjacent vertex $v$ in $S$ with $v$ directed to $u$. The directed domination number of $D$, denoted by…

Combinatorics · Mathematics 2010-10-13 Yair Caro , Michael A. Henning

Let $G$ be a graph with no isolated vertex. In this paper, we study a parameter that is a relaxation of arguably the most important domination parameter, namely the total domination number, $\gamma_t(G)$. A set $S$ of vertices in $G$ is a…

Combinatorics · Mathematics 2014-11-04 Michael A. Henning , Viroshan Naicker

In this paper we initialize the study of independent domination in directed graphs. We show that an independent dominating set of an orientation of a graph is also an independent dominating set of the underlying graph, but that the converse…

Combinatorics · Mathematics 2019-09-12 Michael Cary , Jonathan Cary , Savari Prabhu

The {\em independent domination number} $\gamma^i(G)$ of a graph $G$ is the maximum, over all independent sets $I$, of the minimal number of vertices needed to dominate $I$. It is known \cite{abz} that in chordal graphs $\gamma^i$ is equal…

Combinatorics · Mathematics 2017-09-29 Ron Aharoni , Irina Gorelik

A dominating set of a graph $G$ is a subset $D \subseteq V_G$ 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 the domination number…

Combinatorics · Mathematics 2021-01-18 Joanna Cyman , Michael A. Henning , Jerzy Topp

The distinguishing number (index) $D(G)$ ($D'(G)$) of a graph $G$ is the least integer $d$ such that $G$ has an vertex labeling (edge labeling) with $d$ labels that is preserved only by a trivial automorphism. A set $S$ of vertices in $G$…

Combinatorics · Mathematics 2017-07-20 Saeid Alikhani , Samaneh Soltani

The Grundy domination number, ${\gamma_{\rm gr}}(G)$, of a graph $G$ is the maximum length of a sequence $(v_1,v_2,\ldots, v_k)$ of vertices in $G$ such that for every $i\in \{2,\ldots, k\}$, the closed neighborhood $N[v_i]$ contains a…

Combinatorics · Mathematics 2023-03-10 Gábor Bacsó , Boštjan Brešar , Kirsti Kuenzel , Douglas F. Rall

Let $G$ be a simple and finite graph without isolated vertices. In this paper we introduce and study a new degree sequence derived invariant called the \emph{sub-total domination number}, denoted $\sub_t(G)$. In particular, we show that…

Combinatorics · Mathematics 2017-01-30 Randy Davila

For a graph G, a signed domination function of G is a two-colouring of the vertices of G with colours +1 and -1 such that the closed neighbourhood of every vertex contains more +1's than -1's. This concept is closely related to…

Combinatorics · Mathematics 2009-06-23 A. Poghosyan , V. Zverovich