In this paper we prove that a near difference set with parameters v=2(q+1), k=q, \*= 1 2 (q&1) may be constructed whenever q is an odd prime power. 1996 Academic Press, Inc. (i) For each a ร H the congruence d i &d j #a (mod v) has exactly \* solution pairs (d i , d j ), d i , d j # D.
Relative difference sets with n = 2
โ Scribed by K.T. Arasu; Dieter Jungnickel; Siu Lun Ma; Alexander Pott
- Publisher
- Elsevier Science
- Year
- 1995
- Tongue
- English
- Weight
- 866 KB
- Volume
- 147
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
โฆ Synopsis
We investigate the existence of relative (m, 2, k, 2)-difference sets in a group H x N relative to N. One can think of these as 'liftings' or 'extensions' of (m, k, 22)-difference sets. We have to distinguish between the difference sets and their complements.. In particular, we prove:
--Difference sets with the parameters of the classical Singer difference sets describing PG(d, q) never admit liftings to relative difference sets with n = 2.
--Difference sets of McFarland and Spence type cannot be extended to relative difference sets with n = 2 (with possibly a few exceptions).
--Paley difference sets are not liftable.
--Twin prime power difference sets and their complements never lift.
--Menon-Hadamard difference sets cannot be extended to relative difference set with n = 2 if the order of the difference set is not a solution of a certain PeUian equation.
Our results give strong evidence for the following conjecture: The only non-trivial difference sets which admit extensions to relative difference sets with n = 2 have the parameters of the complements of Singer difference sets with even dimension.
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