1, Semiglobal Cototal Domination on Graphs

A subset D of vertices of a connected graph G is called a semiglobal cototal dominating set if D is a dominating set for G and Gsc and less thanV-Dgreater than has no isolated vertices in G, where Gsc is the semi complementary graph of G. The semiglobal cototal domination number is the minimum cardinality of a semiglobal cototal dominating set of G and is denoted by sgcot (G). In this paper we initiate a study of this new parameter sgcot (G). Some bounds on this parameter are obtained and their exact values for some standard graphs are established.