The total hub number of graphs


Veena Mathad, Ali Mohammed Sahal, S. Kiran




Let $G$ be a graph. A total hub set $S$ of $G$ is a subset of $V(G)$ such that every pair of vertices (whether adjacent or nonadjacent) of $V-S$ are connected by a path, whose all intermediate vertices are in $S$. The total hub number $h_t(G)$ is then defined to be the minimum cardinality of a total hub set of $G$. In this paper, the total hub number for several classes of graphs is computed, bounds in terms of other graph parameters are also determined.