Volume 13 | Issue 4
Volume 13 | Issue 4
Volume 13 | Issue 4
Volume 13 | Issue 4
Volume 13 | Issue 4
In the mathematical discipline of graph theory, a graph labelling is the assignment of labels, traditionally represented by integers, to edges and vertices of a graph. In this case, the graph is called an edge labeled graph. A graph with a pair sum labeling is called a pair sum graph. In this paper we investigate the pair sum label-ing behavior of some trees which are derived from stars and bistars. Finally, we show that all trees of order nine are pair sum graphs