Equality of Domination and Inverse Domination Numbers

T.Tamizh Chelvam1, G.S. Grace Prema2
1Department of Mathematics Manonmaniam Sundaranar University Tirunelveli 627 012 Tamil Nadu, India
2Department of Mathematics St. John’s College Tirunelveli — 627 002 Tamil Nadu, India.

Abstract

A set \(D\) of vertices of a graph \(G = (V, E)\) is a \(\textit{dominating set}\) if every vertex of \(V-D\) is adjacent to at least one vertex in \(D\). The \(\textit{domination number}\) \(\gamma(G)\) is the minimum cardinality of a dominating set of \(G\). A subset of \(V-D\), which is also a dominating set of \(G\), is called an \(\textit{averse dominating set}\) of \(G\) with respect to \(D\). The \(\textit{inverse domination number}\) \(\gamma'(G)\) equals the minimum cardinality of an inverse dominating set \(D\). In this paper, we study classes of graphs whose domination and inverse domination numbers are equal.