On the nonnegative signed domination numbers in graphs
maryam atapour2016, Electronic Journal of Graph Theory and Applications
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Abstract
A nonnegative signed dominating function (NNSDF) of a graph G is a function f from the vertex set V (G) to the set {−1, 1} such that u∈N [v] f (u) ≥ 0 for every vertex v ∈ V (G). The nonnegative signed domination number of G, denoted by γ N N s (G), is the minimum weight of a nonnegative signed dominating function on G. In this paper, we establish some sharp lower bounds on the nonnegative signed domination number of graphs in terms of their order, size and maximum and minimum degree.
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