Results 31 to 40 of about 9,408,041 (287)
The Forcing Domination Number of Hamiltonian Cubic Graphs [PDF]
, 2009 The authors presented a sequence of Hamiltonian cubic graphs whose domination numbers are sharp and in this paper we study forcing domination number for those ...
H. Abdollahzadeh Ahangar +3 more
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Double Roman domination and domatic numbers of graphs
Communications in Combinatorics and Optimization, 2018 A double Roman dominating function on a graph $G$ with vertex set $V(G)$ is defined in \cite{bhh} as a function $f:V(G)\rightarrow\{0,1,2,3\}$ having the property that if $f(v)=0$, then the vertex $v$ must have at least two neighbors assigned 2 ...
L. Volkmann
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The Roman domination and domatic numbers of a digraph [PDF]
Communications in Combinatorics and Optimization, 2019 Let $D$ be a simple digraph with vertex set $V$. A Roman dominating function (RDF) on a digraph $D$ is a function $f: V\rightarrow \{0,1,2\}$ satisfying the condition that every vertex $v$ with $f(v)=0$ has an in-neighbor $u$ with $f(u)=2$. The weight
Z.Xie1, G. Hao, Sh. Wei
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A characterization of trees with equal Roman 2-domination and Roman domination numbers
Communications in Combinatorics and Optimization, 2019 Summary: Given a graph \(G=(V,E)\) and a vertex \(v \in V\), by \(N(v)\) we represent the open neighbourhood of \(v\). Let \(f:V\rightarrow \{0,1,2\}\) be a function on \(G\). The weight of \(f\) is \(\omega(f)=\sum_{v\in V}f(v)\) and let \(V_i=\{v\in V :f(v)=i\}\), for \(i=0,1,2\).
Gonzalez Yero, Ismael +1 more
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On trees with equal Roman domination and outer-independent Roman domination numbers
Communications in Combinatorics and Optimization, 2019 Summary: A Roman dominating function (RDF) on a graph \(G\) is a function \(f : V (G) \to \{0, 1, 2\}\) satisfying the condition that every vertex \(u\) for which \(f(u) = 0\) is adjacent to at least one vertex \(v\) for which \(f(v) = 2\). A Roman dominating function \(f\) is called an outer-independent Roman dominating function (OIRDF) on \(G\) if ...
Sheikholeslami, Seyed Mahmoud +1 more
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Strong equality between the Roman domination and independent Roman domination numbers in trees
Discussiones Mathematicae Graph Theory, 2013 A Roman dominating function (RDF) on a graph G = (V,E) is a function f : V −→ {0, 1, 2} satisfying the condition that every vertex u for which f(u) = 0 is adjacent to at least one vertex v for which f(v) = 2. The weight of an RDF is the value f(V (G)) = P u2V (G) f(u). An RDF f in a graph G is independent if no two vertices assigned positive values are
Mustapha Chellali, Nader Jafari Rad
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On the Quasi-Total Roman Domination Number of Graphs
Mathematics, 2021 Domination theory is a well-established topic in graph theory, as well as one of the most active research areas. Interest in this area is partly explained by its diversity of applications to real-world problems, such as facility location problems ...
Abel Cabrera Martínez +2 more
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On the total Roman domination stability in graphs
AKCE International Journal of Graphs and Combinatorics, 2021 A total Roman dominating function on a graph G is a function satisfying the conditions: (i) every vertex u with f(u) = 0 is adjacent to at least one vertex v of G for which f(v) = 2; (ii) the subgraph induced by the vertices assigned non-zero values has ...
Ghazale Asemian +3 more
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Singed Total Domatic Number of a Graph [PDF]
, 2010 The maximum number of functions in a signed total dominating family on G is the signed total domatic number of G. In this paper, some properties related signed total domatic number and signed total domination number of a graph are studied and found the ...
Shailaja S. Shirkol +2 more
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Roman {2}-Bondage Number of a Graph
Discussiones Mathematicae Graph Theory, 2020 For a given graph G=(V, E), a Roman {2}-dominating function f : V (G) → {0, 1, 2} has the property that for every vertex u with f(u) = 0, either u is adjacent to a vertex assigned 2 under f, or is adjacent to at least two vertices assigned 1 under f. The
Moradi Ahmad +2 more
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