Closed formulas for the total Roman domination number of lexicographic product graphs
نویسندگان
چکیده
Let G be a graph with no isolated vertex and f : V ( ) → {0, 1, 2} function. i = { x ∈ } for every . We say that is total Roman dominating function on if in 0 adjacent to at least one 2 the subgraph induced by 1 ∪ has vertex. The weight of ω ∑ v minimum among all functions domination number , denoted γ t R It known general problem computing NP-hard. In this paper, we show H nontrivial graph, then lexicographic product ∘ given ≥ 2, ξ where parameter defined
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ژورنال
عنوان ژورنال: Ars Mathematica Contemporanea
سال: 2021
ISSN: ['1855-3974', '1855-3966']
DOI: https://doi.org/10.26493/1855-3974.2284.aeb