The Lower Bound of Revised Szeged Index with Respect to Tricyclic Graphs

The revised Szeged index of a graph is defined as Sz* (G) =Sigma(e=uv is an element of E)(n(u)(e) + n(0)(e)/2 (n(v)(e) + n(0)(e)/2) where n(u)(e) and n(v)(e) are, respectively, the number of vertices of G lying closer to vertex u than to vertex v and the number of vertices of G lying closer to vertex v than to vertex u, and n(0)(e) is the number of vertices equidistant to u and v. In the paper, we acquired the lower bound of revised Szeged index among all tricyclic graphs, and the extremal graphs that attain the lower bound are determined.