Bipartite density of cubic graphs: the case of equality
نویسنده
چکیده
Recently, Berman and Zhang (Discrete Math. 260 (2003) 27) obtained an upper bound for the bipartite density of cubic graphs in terms of the smallest eigenvalue of an adjacency matrix and attempted to characterize graphs for which the upper bound is attained. Here we do characterize graphs for which the upper bound is attained, and correct a few errors from Berman and Zhang’s paper. c © 2004 Elsevier B.V. All rights reserved. MSC: 05C50
منابع مشابه
Bipartite density of cubic graphs
We /rst obtain the exact value for bipartite density of a cubic line graph on n vertices. Then we give an upper bound for the bipartite density of cubic graphs in terms of the smallest eigenvalue of the adjacency matrix. In addition, we characterize, except in the case n=20, those graphs for which the upper bound is obtained. c © 2002 Elsevier Science B.V. All rights reserved.
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عنوان ژورنال:
- Discrete Mathematics
دوره 283 شماره
صفحات -
تاریخ انتشار 2004