A lower bound on the Mostar index of tricyclic graphs

Abstract

For a graph G, the Mostar index of G is the sum of |nu-nv| over all edges e = uv of G, where nu denotes the number of vertices of G that have a smaller distance in G to u than to v, and analogously for nv. In this paper, we obtain a lower bound for the Mostar index on tricyclic graphs and identify those graphs that attain the lower bound.