On the Laplacian spectral radius of a tree
نویسنده
چکیده
Let G be a graph; its Laplacian matrix is the difference of the diagonal matrix of its vertex degrees and its adjacency matrix. In this paper, we present a sharp upper bound for the Laplacian spectral radius of a tree in terms of the matching number and number of vertices, and deduce from that the largest few Laplacian spectral radii over the class of trees on a given number of vertices. © 2003 Published by Elsevier Science Inc. AMS classification: 05C50
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