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Properties of the Global Total k-Domination Number

open access: yesMathematics, 2021
A nonempty subset D⊂V of vertices of a graph G=(V,E) is a dominating set if every vertex of this graph is adjacent to at least one vertex from this set except the vertices which belong to this set itself.
Frank A. Hernández Mira   +3 more
doaj   +1 more source

Total Roman Domination Number of Rooted Product Graphs

open access: yesMathematics, 2020
Let G be a graph with no isolated vertex and f:V(G)→{0,1,2} a function. If f satisfies that every vertex in the set {v∈V(G):f(v)=0} is adjacent to at least one vertex in the set {v∈V(G):f(v)=2}, and if the subgraph induced by the set {v∈V(G):f(v)≥1} has ...
Abel Cabrera Martínez   +3 more
doaj   +1 more source

Protection of Lexicographic Product Graphs

open access: yesDiscussiones Mathematicae Graph Theory, 2022
In this paper, we study the weak Roman domination number and the secure domination number of lexicographic product graphs. In particular, we show that these two parameters coincide for almost all lexicographic product graphs. Furthermore, we obtain tight
Klein Douglas J.   +1 more
doaj   +1 more source

Total Domination on Some Graph Operators

open access: yesMathematics, 2021
Let G=(V,E) be a graph; a set D⊆V is a total dominating set if every vertex v∈V has, at least, one neighbor in D. The total domination number γt(G) is the minimum cardinality among all total dominating sets.
José M. Sigarreta
doaj   +1 more source

On the Complexity of Reinforcement in Graphs

open access: yesDiscussiones Mathematicae Graph Theory, 2016
We show that the decision problem for p-reinforcement, p-total rein- forcement, total restrained reinforcement, and k-rainbow reinforcement are NP-hard for bipartite graphs.
Rad Nader Jafari
doaj   +1 more source

Total 2-Rainbow Domination in Graphs

open access: yesMathematics, 2022
A total k-rainbow dominating function on a graph G=(V,E) is a function f:V(G)→2{1,2,…,k} such that (i) ∪u∈N(v)f(u)={1,2,…,k} for every vertex v with f(v)=∅, (ii) ∪u∈N(v)f(u)≠∅ for f(v)≠∅.
Huiqin Jiang, Yongsheng Rao
doaj   +1 more source

Some notes on the isolate domination in graphs

open access: yesAKCE International Journal of Graphs and Combinatorics, 2017
A subset of vertices of a graph is a dominating set of if every vertex in has a neighbor in . The domination number is the minimum cardinality of a dominating set of . A dominating set is an isolate dominating set if the induced subgraph has at least one
Nader Jafari Rad
doaj   +1 more source

Minus total domination in graphs [PDF]

open access: yesCzechoslovak Mathematical Journal, 2009
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Xing, Hua-Ming, Liu, Hai-Long
openaire   +2 more sources

Lower Bounds for the Total Distance $k$-Domination Number of a Graph

open access: yesTheory and Applications of Graphs
For $k \geq 1$ and a graph $G$ without isolated vertices, a \emph{total distance $k$-dominating set} of $G$ is a set of vertices $S \subseteq V(G)$ such that every vertex in $G$ is within distance $k$ to some vertex of $S$ other than itself.
Randy R. Davila
doaj   +1 more source

On a conjecture concerning total domination subdivision number in graphs

open access: yesAKCE International Journal of Graphs and Combinatorics, 2021
Let be the total domination number and let be the total domination subdivision number of a graph G with no isolated vertex. In this paper, we show that for some classes of graphs G, which partially solve the conjecture presented by Favaron et al.
S. Kosari   +5 more
doaj   +1 more source

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