L-Borderenergetic Graphs and Normalized Laplacian Energy
نویسنده
چکیده
The Laplacian and normalized Laplacian energy of G are given by expressions EL(G) = ∑n i=1 |μi − d|, EL(G) = ∑n i=1 |λi − 1|, respectively, where μi and λi are the eigenvalues of Laplacian matrix L and normalized Laplacian matrix L of G. An interesting problem in spectral graph theory is to find graphs {L,L}−noncospectral with the same E{L,L}(G). In this paper, we present graphs of order n, which are L-borderenergetic (in short, EL(G) = 2n− 2) and graphs L-noncospectral with the same normalized Laplacian energy. (Received November 4, 2016)
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