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Twisted product of cocycles and factorization of semi-regular relative difference sets

✍ Scribed by Yu Qing Chen

Publisher: John Wiley and Sons
Year: 2008
Tongue: English
Weight: 152 KB
Volume: 16
Category: Article
ISSN: 1063-8539
DOI: 10.1002/jcd.20195

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✦ Synopsis

Abstract

In this article, we introduce what we call twisted Kronecker products of cocycles of finite groups and show that the twisted Kronecker product of two cocycles is a Hadamard cocycle if and only if the two cocycles themselves are Hadamard cocycles. This enables us to generalize some known results concerning products and factorizations of central semi‐regular relative difference sets. © 2008 Wiley Periodicals, Inc. J Combin Designs 16: 431–441, 2008

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