Graphs with fourth Laplacian eigenvalue less than two
نویسنده
چکیده
In this paper, all connected graphs with the fourth largest Laplacian eigenvalue less than two are determined, which are used to characterize all connected graphs with exactly three Laplacian eigenvalues no less than two. Moreover, we determine bipartite graphs such that the adjacency matrices of their line graphs have exactly three nonnegative eigenvalues. © 2003 Elsevier Ltd. All rights reserved. MSC: 05C50; 05C75; 15A18
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ورودعنوان ژورنال:
- Eur. J. Comb.
دوره 24 شماره
صفحات -
تاریخ انتشار 2003