一类具有(2t+1)-匹配的树的第二大特征值的下界

摘要

The characteristic polynomials of two classes of trees were calculated. A method for comparing the largest roots of two monic polynomials was introduced. A class of tree matching (2t+1) was investigated with the mentioned method and a lower bound for the second largest eigenvalue of the class was obtained. The work improves the boundary of theory of eigenvalue.%计算了两类树的特征多项式,介绍了一个比较两个首一多项式的最大根的方法,并应用这个方法研究了一类具有 (2t+1)-匹配的树,得到了这类树的第二大特征值的一个下界,进一步完善了特征值的界理论.