Quadruple Roman Domination in Trees
نویسندگان
چکیده
This paper is devoted to the study of quadruple Roman domination in trees, and it a contribution Special Issue “Theoretical computer science discrete mathematics” Symmetry. For any positive integer k, [k]-Roman dominating function ([k]-RDF) simple graph G from vertex set V {0,1,2,…,k+1} if for u?V with f(u)<k, ?x?N(u)?{u}f(x)?|{x?N(u):f(x)?1}|+k, where N(u) open neighborhood u. The weight [k]-RDF value ?v?Vf(v). minimum called number ?[kR](G) G. In this paper, we establish sharp upper lower bounds on ?[4R](T) nontrivial trees T characterize extremal trees.
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ژورنال
عنوان ژورنال: Symmetry
سال: 2021
ISSN: ['0865-4824', '2226-1877']
DOI: https://doi.org/10.3390/sym13081318