Dominating Sets With at Most \(k\) Components

B.L. Hartnell1, P.D. Vestergaard2
1Department of Mathematics and Computing Science Saint Mary’s University Halifax, N.S. Canada B3H 3C3
2Department of Mathematics Aalborg University Fredrik Bajers Vej 7G DK-9220 Aalborg @ Denmark

Abstract

A connected dominating set \(D\) of a graph \(G\) has the property that not only does \(D\) dominate the graph but the subgraph induced by the vertices of \(D\) is also connected. We generalize this concept by allowing the subgraph induced by \(D\) to contain at most \(k\) components and examine the minimum possible order of such a set. In the case of trees, we provide lower and upper bounds and a characterization for those trees which achieve the former.