The Wiener Index of Unicyclic Graphs with Girth and Matching Number

Ya-Hong Chen1, Xiao-Dong Zhang2
1 Teacher Education College, Lishui University Lishui, Zhejiang 323000, PR China
2Department of Mathematics, Shanghai Jiao Tong University 800 Dongchuan road, Shanghai, 200240, P.R. China

Abstract

In this paper, we investigate how the Wiener index of unicyclic graphs varies with graph operations. These results are used to present a sharp lower bound for the Wiener index of unicyclic graphs of order \(n\) with girth \(g\) and matching number \(\beta \geq \frac{3g}{2}\), Moreover, we characterize all extremal graphs which attain the lower bound.