Bounds on the disjunctive domination number of a tree
نویسندگان
چکیده
A set D of vertices in a graph G is disjunctive dominating if every vertex not adjacent to or has at least two distance 2 from it . The domination number, γ d ( ), the minimum cardinality We show that T tree order n with l leaves and s support vertices, then n-l +3/4≤ )≤ n+l +s/4. Moreover, we characterize families trees which attain these bounds.
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ژورنال
عنوان ژورنال: Rairo-operations Research
سال: 2022
ISSN: ['1290-3868', '0399-0559']
DOI: https://doi.org/10.1051/ro/2022105