图的laplace谱半径的一个上界

A Upper bounds of Laplacian Spectral radius of Graphs

本文利用了图的度平方和的不等式,得到一般简单连通无向图的laplace谱半径的一个新上界μ(G)≤2m+(n-2)m(mn+2n-4m-2)/n-1等式成立当且仅当G为星图k_(1,n-1) 。

This paper by using the inequalities on the sum of the squares of the degrees of a graph, we get a sharp upper bound for the Laplace spectral radius of simple connected undirected graphs：μ（G）≤2m＋√（n-s）m（mn＋2n-4m-2）/（n-1） equality holds if and only ifG is star graph k1,n-1.