【摘要】 <正>1引言若A=(a_ij),其中a_ij≥0,我们则称A为非负矩阵.众所周知,A有一个非负的特征根,其绝对值不小于其他任意的特征根,称之为A的Perron根,记作r（A）.许多学者已经给出了非负矩阵或正矩阵r（A）的界.由Perron-Frobenius定理,可知:min S_i≤r（A）≤maxS_i,（1.1）其中（?）更多还原

【Abstract】 Increasing sequence of lower bounds for the Perron root of nonnegative matrices are presented.Two of them are for any nonnegative matrices and the other one is for nonnegative matrices that satisfy some conditions.The comparison of the new sequence with the known one is presented by numerical examples.更多还原