Results 51 to 60 of about 152,920 (311)
Roman Domination in Complementary Prism Graphs [PDF]
, 2012 A Roman domination function on a complementary prism graph GGc is a function f : V [ V c ! {0, 1, 2} such that every vertex with label 0 has a neighbor with label 2. The Roman domination number R(GGc) of a graph G = (V,E) is the minimum of Px2V [V c f(x)
Chaitra, V., Chaluvaraju, B.
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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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On the roman domination number of generalized Sierpiński graphs [PDF]
Filomat, 2017 A map f : V?(0,1,2) is a Roman dominating function on a graph G = (V,E) if for every vertex v ? V with f(v)=0, there exists a vertex u, adjacent to v, such that f(u)=2. The weight of a Roman dominating function is given by f(V)=?u?V f(u). The minimum weight among all Roman dominating functions on G is called the Roman domination number of G.
Ramezani, F. +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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New Bounds on the Triple Roman Domination Number of Graphs
Journal of mathematics, 2022 In this paper, we derive sharp upper and lower bounds on the sum γ3RG+γ3RG¯ and product γ3RGγ3RG¯ , where G¯ is the complement of graph G. We also show that for each tree T of order n ≥ 2, γ[3R](T) ≤ 3n + s(T)/2 and γ[3R](T) ≥ ⌈4(n(T) + 2 − ℓ(T))/3 ...
M. Hajjari +4 more
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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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Rainbow domination and related problems on some classes of perfect graphs [PDF]
, 2015 Let $k \in \mathbb{N}$ and let $G$ be a graph. A function $f: V(G) \rightarrow 2^{[k]}$ is a rainbow function if, for every vertex $x$ with $f(x)=\emptyset$, $f(N(x)) =[k]$.
A Bertossi +23 more
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Roman game domination subdivision number of a graph [PDF]
Transactions on Combinatorics, 2013 A {em Roman dominating function} on a graph $G = (V ,E)$ is a function $f : Vlongrightarrow {0, 1, 2}$ satisfying the condition that every vertex $v$ for which $f (v) = 0$ is adjacent to at least one vertex $u$ for which $f (u) = 2$. The {em weight} of a
Jafar Amjadi +3 more
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Total double Roman domination in graphs [PDF]
Communications in Combinatorics and Optimization, 2020 Let $G$ be a simple graph with vertex set $V$. A double Roman dominating function (DRDF) on $G$ is a function $f:V\rightarrow\{0,1,2,3\}$ satisfying that if $f(v)=0$, then the vertex $v$ must be adjacent to at least two vertices assigned $2$ or one ...
Guoliang Hao +2 more
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