Total restrained domination in unicyclic graphs
نویسندگان
چکیده
Let G = (V,E) be a graph. A set S ⊆ V is a total restrained dominating set if every vertex in V is adjacent to a vertex in S and every vertex of V −S is adjacent to a vertex in V −S. The total restrained domination number of G, denoted by γtr(G), is the minimum cardinality of a total restrained dominating set of G. A unicyclic graph is a connected graph that contains precisely one cycle. We show that if U is a unicyclic graph of order n, then γtr(U) ≥ dn2 e, and provide a characterization of graphs achieving this bound.
منابع مشابه
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