Results 31 to 40 of about 1,275 (240)
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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Perfect domination, Roman domination and perfect Roman domination in lexicographic product graphs [PDF]
, 2022 The aim of this paper is to obtain closed formulas for the perfect dominationnumber, the Roman domination number and the perfect Roman domination number oflexicographic product graphs.
Garcia-Gomez, C. +2 more
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Extremal Graphs for a Bound on the Roman Domination Number
Discussiones Mathematicae Graph Theory, 2020 A Roman dominating function on a graph G = (V, E) is a function f:V (G) → {0, 1, 2} such that every vertex u for which f(u) = 0 is adjacent to at least one vertex v with f(v) = 2. The weight of a Roman dominating function is the value w(f) = Σu∈V(G)f(u).
Bouchou Ahmed +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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Bounds on the Double Italian Domination Number of a Graph
Discussiones Mathematicae Graph Theory, 2022 For a graph G, a Roman {3}-dominating function is a function f : V → {0, 1, 2, 3} having the property that for every vertex u ∈ V, if f(u) ∈ {0, 1}, then f(N[u]) ≥ 3.
Azvin Farzaneh, Rad Nader Jafari
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Weak signed Roman domination in graphs [PDF]
Communications in Combinatorics and Optimization, 2020 A weak signed Roman dominating function (WSRDF) of a graph $G$ with vertex set $V(G)$ is defined as a function $f:V(G)\rightarrow\{-1,1,2\}$ having the property that $\sum_{x\in N[v]}f(x)\ge 1$ for each $v\in V(G)$, where $N[v]$ is the closed ...
Lutz Volkmann
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Calculating Modern Roman Domination of Fan Graph and Double Fan Graph [PDF]
Journal of Applied Sciences and Nanotechnology, 2022 This paper is concerned with the concept of modern Roman domination in graphs. A Modern Roman dominating function on a graph is labeling such that every vertex with label 0 is adjacent to two vertices; one of them of label 2 and the other of label 3 and ...
Saba Salah, Ahmed Omran, Manal Al-Harere
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Trees with equal Roman {2}-domination number and independent Roman {2}-domination number [PDF]
, 2019 A Roman {2}-dominating function (R{2}DF) 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 either at least one vertex v with f(v) = 2 or two vertices v1, v2 with f(v1) = f ...
Zepeng Li +3 more
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New complexity results on Roman {2}-domination [PDF]
, 2023 The study of a variant of Roman domination was initiated by Chellali et al. [Discrete Appl. Math. 204 (2016) 22–28]. Given a graph G with vertex set V, a Roman {2}-dominating function f : V → {0, 1, 2} has the property that for every vertex v ∈ V with f ...
Leoni, Valeria Alejandra +3 more
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