THE VERTEX AND EDGE PI INDICES OF GENERALIZED HIERARCHICAL PRODUCT OF GRAPHS
THE VERTEX AND EDGE PI INDICES OF GENERALIZED HIERARCHICAL PRODUCT OF GRAPHS
Pattabiraman and Paulraja [K. Pattabiraman, P. Paulraja, Vertex and edge PI indices of the generalized hierarchical product of graphs, Discrete Appl. Math. 160 (2012) 1376- 1384] obtained exact formulas for the vertex and edge PI indices of generalized hierarchical product of graphs. The aim of this note is to improve …