Finite Euclidean graphs over ℤ2r are non-Ramanujan
نویسنده
چکیده
Graphs are attached to 2r where 2r is the ring with 2 r elements using an analogue of Euclidean distance. M.R. DeDeo (2003) showed that these graphs are non-Ramanujan for r 4. In this paper, we will show that finite Euclidean graphs attached to 2r are non Ramanujan for r 2 except for r = 2 and d = 2, 3. Together with the results in Medrano et al. (1998), this implies that finite Euclidean graphs over pr for p prime are non-Ramanujan except for the smallest cases.
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ورودعنوان ژورنال:
- Australasian J. Combinatorics
دوره 43 شماره
صفحات -
تاریخ انتشار 2009