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When a digraph and its line digraph are connected and cospectral

✍ Scribed by Fuji Zhang; Guoning Lin

Publisher
Elsevier Science
Year
1998
Tongue
English
Weight
266 KB
Volume
184
Category
Article
ISSN
0012-365X

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✦ Synopsis

In this paper we characterize all digraphs each one of which is cospectral with its line digraph and both the digraph and its line digraph are connected. Some related enumeration problems are also considered. From these results we can see that there are arbitrarily large sets of cospectral digraphs. (~) 1998 Elsevier Science B.V. All rights reserved In 1960, Harary and Norman [3] introduced the concept of line digraph. For a digraph

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