A New Upper Bound on the Global Defensive Alliance Number in Trees
نویسندگان
چکیده
A global defensive alliance in a graph G = (V,E) is a dominating set S satisfying the condition that for every vertex v ∈ S, |N [v] ∩ S| ≥ |N(v) ∩ (V − S)|. In this note, a new upper bound on the global defensive alliance number of a tree is given in terms of its order and the number of support vertices. Moreover, we characterize trees attaining this upper bound.
منابع مشابه
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عنوان ژورنال:
- Electr. J. Comb.
دوره 18 شماره
صفحات -
تاریخ انتشار 2011