an:01436244
Zbl 0956.05026
de Launey, Warwick; Flannery, D. L.; Horadam, K. J.
Cocyclic Hadamard matrices and difference sets
EN
Discrete Appl. Math. 102, No. 1-2, 47-61 (2000).
00064417
2000
j
05B20 05B10 20J06 05B05
Hadamard matrix; difference set; perfect binary array; cocycle
The authors explain the connection between (relative) difference sets, cocyclic Hadamard matrices, cocycles, coboundaries and perfect binary arrays. In particular, they mention the interesting conjecture that for any \(t\), cocyclic Hadamard matrices of order \(4t\) exist. The authors show that many of the known families of Hadamard matrices are actually families of cocyclic Hadamard matrices.
Alexander Pott (Magdeburg)