Disjunctive Total Domination In Harary Graphs

Abstract

Let G be a graph. A set S of vertices in G is a disjunctive total dominating set of G if every vertex is adjacent to a vertex of S or has at least two vertices in S at distance two from it. The disjunctive total domination number, gamma(d)(t)(G), is the minimum cardinality of such a set. In this paper, we determine disjunctive total domination number of Harary graph H-k,H-n for all k and n.