On the (2, 2)-domination number of trees
نویسندگان
چکیده
Let γ(G) and γ2,2(G) denote the domination number and (2, 2)domination number of a graph G, respectively. In this paper, for any nontrivial tree T , we show that 2(γ(T )+1) 3 ≤ γ2,2(T ) ≤ 2γ(T ). Moreover, we characterize all the trees achieving the equalities.
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ورودعنوان ژورنال:
- Discussiones Mathematicae Graph Theory
دوره 30 شماره
صفحات -
تاریخ انتشار 2010