On trees with double domination number equal to total domination number plus one
نویسنده
چکیده
A total dominating set of a graph G is a set D of vertices of G such that every vertex of G has a neighbor in D. A vertex of a graph is said to dominate itself and all of its neighbors. A double dominating set of a graph G is a set D of vertices of G such that every vertex of G is dominated by at least two vertices of D. The total (double, respectively) domination number of a graph G is the minimum cardinality of a total (double, respectively) dominating set of G. We characterize all trees with double domination number equal to total domination number plus one.
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ورودعنوان ژورنال:
- Ars Comb.
دوره 102 شماره
صفحات -
تاریخ انتشار 2011