【摘要】 通过对Q-阵及其特征值的分析刻划,得到了Q谱谱半径的一些可达上界和可达下界.最后给出了Lapla-cian谱谱半径的一个下界.更多还原

【Abstract】 We have obtained some sharp upper and lower bounds of the spectral radius of a Q-spectrum,corresponding to the Q-matrix.The Q-matrix is a nonnegative,symmetric,irreducible(if G is connected) and positive definite(if G is not empty).Finally,we give a lower bound of the spectral radius of the Laplacian spectrum.更多还原