Bounds on the Distance Two-Domination Number of a Graph
نویسندگان
چکیده
For a graph G = (V , E), a subset D V ðGÞ is said to be distance two-dominating set in G if for each vertex u 2 V D, there exists a vertex v 2 D such that dðu; vÞ 2. The minimum cardinality of a distance two-dominating set in G is called a distance twodomination number and is denoted by c2ðGÞ. In this note we obtain various upper bounds for c2ðGÞ and characterize the classes of graphs attaining these bounds.
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ورودعنوان ژورنال:
- Graphs and Combinatorics
دوره 18 شماره
صفحات -
تاریخ انتشار 2002