The Laplacian spectrum of a mixed graph
نویسندگان
چکیده
In this paper, we discuss some properties of relations between a mixed graph and its line graph, which are used to characterize the Laplacian spectrum of a mixed graph. Then we present two sharp upper bounds for the Laplacian spectral radius of a mixed graph in terms of the degrees and the average 2-degrees of vertices and we also determine some extreme graphs which attain these upper bounds. © 2002 Elsevier Science Inc. All rights reserved. AMS classification: 05C50; 15A42
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تاریخ انتشار 2002