On the Sum of Powers of Normalized Laplacian Eigenvalues of Graphs
نویسندگان
چکیده
For a graph G without isolated vertices and a real α = 0, we introduce a new graph invariant s∗α (G)the sum of the αth power of the non-zero normalized Laplacian eigenvalues of G. Recently, the cases α = 2 and −1 have appeared in various problems in the literature. Here, we present some lower and upper bounds of s∗α (G) for a connected graph G, where α = 0, 1. We also discuss the case α = −1.
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تاریخ انتشار 2012