Non-Ramanujancy of Euclidean graphs of order 2r
نویسنده
چکیده
Graphs are attached to the n-dimensional space Z 2r where Z2r is the ring with 2 r elements using an analogue of Euclidean distance. The graphs are shown to be non-Ramanujan for r=4. Comparisons are made with Euclidean graphs attached to Z pr for p an odd prime. The percentage of non-zero eigenvalues of the adjacency operator attached to these 1nite Euclidean graphs is shown to tend to zero as n tends to in1nity. c © 2002 Elsevier Science B.V. All rights reserved.
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عنوان ژورنال:
- Discrete Mathematics
دوره 265 شماره
صفحات -
تاریخ انتشار 2003