Normal sequences of lengths n = 18, 19 are constructed. It is proved through an exhaustive search that normal sequences do not exist for n = 17,21,22,23. Marc Gysin has shown that normal sequences do not exist for n = 24. So the first unsettled case is n = 27. Base sequences of lengths 2n -1, 2n -1. n. n are constructed for all decompositions of 6n -2 into four squares for n = 2.4.6 ..... 20 and some base sequences for n = 22.24 are also given. So T-sequences (T-matrices) of length 71 are constructed here for the first time. This gives new Hadamard matrices of orders 213, 781, 1349, 1491, 1633, 2059, 2627, 2769, 3479, 3763, 4331, 4899, 5467, 5609, 5893, 6177, 6461,6603, 6887, 7739, 8023, 8591, 9159, 9443, 9727, 9869.
Disciplines
Physical Sciences and Mathematics
Publication DetailsChristos Koukouvinos, Stratis Kounias, Jennifer Seberry, C. H. Yang, Joel Yang, On sequences with zero autocorrelation, Designs, Codes and Cryptography, 4, (1994), 327-340. This journal article is available at Research Online: http://ro.uow.edu.au/infopapers/1090 Designs, Codes and Cryptography, 4, 327-340 (1994 Base sequences of lengths 2n -I. 2n -I. n. n are constructed for all decompositions of 6n -2 into four squares for n = 2.4.6 ..... 20 and some base sequences for n = 22.24 are also given. So T-sequences (T-matrices) of length 71 are constructed here for the first time. This gives new Hadamard matrices of orders 213.) © 1994 Kluwer Academic Publishers, Boston. Manufactured in The Netherlands.
On Sequences with Zero Autocorrelation