A linear algorithm for obtaining the Laplacian eigenvalues of a cograph

Abstract

In this paper, we give a linear algorithm for obtaining the Laplacian eigenvalues of a cograph. This approach is more efficient as there is no need to directly compute the eigenvalues of Laplacian matrix related to this class of graph. As an application, we use this algorithm as a tool for obtaining a closed formula for the number of spanning trees of a cograph.