Global defensive k-alliances in graphs
نویسندگان
چکیده
Let Γ = (V,E) be a simple graph. For a nonempty set X ⊆ V , and a vertex v ∈ V , δX(v) denotes the number of neighbors v has in X. A nonempty set S ⊆ V is a defensive k-alliance in Γ = (V,E) if δS(v) ≥ δS̄(v)+k, ∀v ∈ S. A defensive k-alliance S is called global if it forms a dominating set. The global defensive k-alliance number of Γ, denoted by γ k(Γ), is the minimum cardinality of a defensive k-alliance in Γ. We study the mathematical properties of γ k(Γ).
منابع مشابه
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ورودعنوان ژورنال:
- Discrete Applied Mathematics
دوره 157 شماره
صفحات -
تاریخ انتشار 2009