Ordering Quasi-tree Graphs on n Vertices by Their Spectral Radii
Ordering Quasi-tree Graphs on n Vertices by Their Spectral Radii

DOI：

 作者 单位 E-mail 郭曙光 盐城师范学院 ychgsg@163.com 罗可 青海师范大学 luoke_hn@163.com 林震 青海师范大学 LNLinZhen@163.com

A connected graph $G=(V,E)$ is called a quasi-tree graph, if there exists a vertex $v_0\in V(G)$ such that $G-v_0$ is a tree. Liu and Lu [Linear Algebra Appl. 428 (2008) 2708-2714] determined the maximal spectral radius together with the corresponding graph among all quasi-tree graphs on $n$ vertices. In this paper, we extend their result, and determine the second to the fifth largest spectral radii together with the corresponding graphs among all quasi-tree graphs on $n$ vertices.