A note on distance domination numbers of graphs
نویسندگان
چکیده
Let k be a positive integer and G = (V,E) a connected graph of order n. A set D ⊆ V is called a distance k-dominating set of G if each x ∈ V (G)−D is within distance k from some vertex of D. The k-domination number of G, denoted by γk(G), is the minimum cardinality over all distance k-dominating sets. Determining γk(G) has a significant impact on an efficient design of routing protocols in networks and, moreover, computing γk(G) is NP-hard. This paper establishes some upper bounds for γk(G) and improves some known results.
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ورودعنوان ژورنال:
- Australasian J. Combinatorics
دوره 43 شماره
صفحات -
تاریخ انتشار 2009