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Total Roman domination subdivision number in graphs [PDF]

open access: yesCommunications in Combinatorics and Optimization, 2020
A {\em Roman dominating function} on a graph $G$ is a function $f:V(G)\rightarrow \{0,1,2\}$ satisfying the condition that every vertex $u$ for which $f(u)=0$ is adjacent to at least one vertex $v$ for which $f(v)=2$.
Jafar Amjad
doaj   +1 more source

On a Relation between the Perfect Roman Domination and Perfect Domination Numbers of a Tree

open access: yesMathematics, 2020
A dominating set in a graph G is a set of vertices S ⊆ V ( G ) such that any vertex of V − S is adjacent to at least one vertex of S .
Zehui Shao   +4 more
doaj   +1 more source

A note on the Roman domatic number of a digraph [PDF]

open access: yesCommunications in Combinatorics and Optimization, 2020
A {\em Roman dominating function} on a digraph $D$ with vertex set $V(D)$ is a labeling $f\colon V(D)\to \{0, 1, 2\}$ such that every vertex with label $0$ has an in-neighbor with label $2$. A set $\{f_1,f_2,\ldots,f_d\}$ of Roman dominating functions
Lutz Volkmann, D. Meierling
doaj   +1 more source

Progress on Roman and Weakly Connected Roman Graphs

open access: yesMathematics, 2021
A graph G for which γR(G)=2γ(G) is the Roman graph, and if γRwc(G)=2γwc(G), then G is the weakly connected Roman graph. In this paper, we show that the decision problem of whether a bipartite graph is Roman is a co-NP-hard problem. Next, we prove similar
Joanna Raczek, Rita Zuazua
doaj   +1 more source

On the Roman Edge Domination Number of a Graph [PDF]

open access: yes, 2010
Let G be a simple graph with vertex set V (G) and edge set E(G)
K. Ebadi   +5 more
core   +1 more source

A note on the double Roman domination number of graphs [PDF]

open access: yes, 2020
summary:For a graph $G=(V,E)$, a double Roman dominating function is a function $f\colon V\rightarrow \{0,1,2,3\}$ having the property that if $f(v)=0$, then the vertex $v$ must have at least two neighbors assigned $2$ under $f$ or one neighbor with $f(w)
Chen, Xue-Gang
core   +1 more source

On Roman, Global and Restrained Domination in Graphs [PDF]

open access: yes, 2010
In this paper, we present new upper bounds for the global domination and Roman domination numbers and also prove that these results are asymptotically best possible.
Zverovich, Vadim   +3 more
core   +1 more source

On the Outer Independent Double Roman Domination Number [PDF]

open access: yesBulletin of the Iranian Mathematical Society, 2021
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Doost Ali Mojdeh   +3 more
openaire   +1 more source

Triple Connected Domination Number of a Graph [PDF]

open access: yes, 2012
The concept of triple connected graphs with real life application was introduced by considering the existence of a path containing any three vertices of a graph G.
Selvam Avadayappan   +7 more
core   +1 more source

ALGORITHMIC ASPECTS OF ROMAN GRAPHS [PDF]

open access: yesJournal of Algebraic Systems, 2021
Let $G=(V, E)$ be a graph. A set $S \subseteq V$ is called a dominating set of $G$ if for every $v\in V-S$ there is at least one vertex $u \in N(v)$ such that $u\in S$.
A. Poureidi
doaj   +1 more source

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