On Distance-Two Domination of Composition of Graphs
نویسنده
چکیده
For a graph ( ) , G V E = , let and denote the set of vertices that are at distance one and two from respectively. A subset 1( ) N v 2 ( ) N v v ( ) D V G ⊆ is said to be a -dominating set of if every vertex 3,2,1 D G v V ∈ satisfies ( ) 3 D w v ≥ where ( ) D w v = 3 { } v D ∩ + 2 ( ) 1 N v D ∩ + ( ) 2 N v D ∩ . The minimum cardinality of a -dominating set of , denoted as 3,2,1 D G ( ) 3,2,1 G γ , is called the -domination number of . In this paper we obtained the -domination number of the composition of a cycle with a path and a cycle with a cycle. 3,2,1 D G
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تاریخ انتشار 2010