caa a22 4500 477040896 CHVBK 20180405111317.0 cr unu---uuuuu 170330e19961001xx s 000 0 eng 10.1023/A:1027342024177 doi (NATIONALLICENCE)springer-10.1023/A:1027342024177 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 adihedral group of order 2p, where pis an odd integer. Let Z D 2p be the group ringof D 2p over the ring Z of integers.We identify elements of Z D 2p and their matricesof the regular representation of Z D 2p . Recently we characterized the Hadamard matrices of order 28 ([6]) and ([7]). There are exactly 487 Hadamardmatrices of order 28, up to equivalence. In thesematrices there exist matrices with some interesting properties.That is, these are constructed by elements of ZD 6.We discuss relation of Z D 2p and Hadamard matricesof order n=8p+4, and give some examples of Hadamardmatrices constructed by dihedral groups. Kluwer Academic Publishers, 1996 Dihedral groups nationallicence Hadamard matrices nationallicence Designs, Codes and Cryptography Kluwer Academic Publishers 9/1(1996-10-01), 71-77 0925-1022 9:1<71 1996 9 10623 https://doi.org/10.1023/A:1027342024177 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1027342024177 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(1996-10-01), 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