On the p-domination number of cactus graphs
نویسندگان
چکیده
Let p be a positive integer and G = (V;E) a graph. A subset S of V is a p-dominating set if every vertex of V S is dominated at least p times. The minimum cardinality of a p-dominating set a of G is the p-domination number p(G): It is proved for a cactus graph G that p(G) 6 (jV j+ jLp(G)j+c(G))=2; for every positive integer p > 2; where Lp(G) is the set of vertices of G of degree at most p 1 and c(G) is the number of odd cycles in G:
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عنوان ژورنال:
- Discussiones Mathematicae Graph Theory
دوره 25 شماره
صفحات -
تاریخ انتشار 2005