caa a22 4500 477040829 CHVBK 20180405111317.0 cr unu---uuuuu 170330e19960801xx s 000 0 eng 10.1007/BF00169775 doi (NATIONALLICENCE)springer-10.1007/BF00169775 Kimura Hiroshi Department of Mathematics, Ehime University, 790-77, Matsuyama, Japan aut Hadamard matrices and dihedral groups [Elektronische Daten] [Hiroshi Kimura] Let D 2p be a dihedral group of order 2p, where p is an odd integer. Let ZD 2p be the group ring of D 2p over the ring Z of integers. We identify elements of ZD 2p and their matrices of the regular representation of ZD 2p . Recently we characterized the Hadamard matrices of order 28 ([6] and [7]). There are exactly 487 Hadamard matrices of order 28, up to equivalence. In these matrices there exist matrices with some interesting properties. That is, these are constructed by elements of ZD 6. We discuss relation of ZD 2p and Hadamard matrices of order n=8p+4, and give some examples of Hadamard matrices constructed by dihedral groups. Kluwer Academic Publishers, 1996 Designs, Codes and Cryptography Kluwer Academic Publishers 9/1(1996-08-01), 71-77 0925-1022 9:1<71 1996 9 10623 https://doi.org/10.1007/BF00169775 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00169775 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Kimura Hiroshi Department of Mathematics, Ehime University, 790-77, Matsuyama, Japan aut NATIONALLICENCE 773 0- Designs, Codes and Cryptography Kluwer Academic Publishers 9/1(1996-08-01), 71-77 0925-1022 9:1<71 1996 9 10623 Metadata rights reserved Springer special CC-BY-NC licence nationallicence SWISSBIB 477040829 BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer