A note on the second largest eigenvalue of a tree with perfect matchings Original Research Article

In this paper, we present an upper bound for the second largest eigenvalue of a tree on n=2k=4t (tgreater-or-equal, slanted2) vertices with perfect matchings. At the same time, the few largest second largest eigenvalues over the class of trees on n=2k=4t (tgreater-or-equal, slanted2) vertices with perfect matchings are also obtained.