A Note on Disjoint Dominating Sets in Graphs
نویسنده
چکیده
The disjoint domination number γγ(G) of a graph G is the minimum cardinality of the union of two disjoint dominating sets in G. The disjoint independent domination number of a graph G is the minimum cardinality of the union of two disjoint independent dominating sets in G. In this paper we study these two parameters. We determine the value of γγ(G) for several graphs and give partial answers to some open problems posed in [5]. Mathematics Subject Classification: 05C69
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