an:05349666
Zbl 1148.05015
Chen, Yu Qing
Twisted product of cocycles and factorization of semi-regular relative difference sets
EN
J. Comb. Des. 16, No. 5, 431-441 (2008).
00229857
2008
j
05B10
relative difference set; generalized Hadamard matrix; Hadamard cocycle; divisible; design
Summary: 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.