Global minus Domination in Graphs
نویسندگان
چکیده
A function f : V (G) → {−1, 0, 1} is a minus dominating function if for every vertex v ∈ V (G), ∑ u∈N [v] f(u) ≥ 1. A minus dominating function f of G is called a global minus dominating function if f is also a minus dominating function of the complement G of G. The global minus domination number γ− g (G) of G is defined as γ − g (G) = min{ ∑ v∈V (G) f(v) | f is a global minus dominating function of G}. In this paper we initiate the study of the global minus domination number in graphs and we establish lower and upper bounds for the global minus domination number.
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