Some Results on the Strong Roman Domination Number of Graphs

Autor: Akram Mahmoodi, Sakineh Nazari-Moghaddam, Afshin Behmaram
Jazyk: angličtina
Rok vydání: 2020
Předmět:
Zdroj: Mathematics Interdisciplinary Research, Vol 5, Iss 3, Pp 259-277 (2020)
Druh dokumentu: article
ISSN: 2476-4965
DOI: 10.22052/mir.2020.225635.1205
Popis: Let G=(V,E) be a finite and simple graph of order n and maximum‎ ‎degree Δ(G)‎. ‎A strong Roman dominating function on a‎ ‎graph G is a function f‎:V (G)→{0‎, ‎1,… ,‎[Δ(G)/2 ]‎+ ‎1} satisfying the condition that every‎ ‎vertex v for which f(v)=0 is adjacent to at least one vertex u ‎for which‎ f(u) ≤ 1‎+ [(1/2)| N(u) ∩ V0| ], ‎where V0={v ∊ V | f(v)=0}. The minimum of the‎ values ∑v∊ V f(v), ‎taken over all strong Roman dominating‎ ‎functions f of G‎, ‎is called the strong Roman domination‎ ‎number of G and is denoted by γStR(G)‎. ‎In this paper we‎ ‎continue the study of strong Roman domination number in graphs‎. ‎In‎ particular‎, ‎we present some sharp bounds for γStR(G) and‎ we determine the strong Roman domination number of some graphs‎.
Databáze: Directory of Open Access Journals