Publication: Hadamard matrices of small order and Yang conjecture

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Title	Hadamard matrices of small order and Yang conjecture
Authors/Editors*	D.Z. Djokovic
Where published*	Journal of Combinatorial Designs
How published*	Journal
Year*	2010
Volume	18
Number	4
Pages	254-259
Publisher	Wiley Periodicals, Inc.
Keywords	Base sequences, normal and near-normal sequences, T-sequences, orthogonal designs, Williamson-type matrices, Yang conjecture
Link	arXiv:0912.5091v1 [math.CO] 27 Dec 2009
Abstract	We show that 138 odd values of n<10000 for which a Hadamard matrix of order 4n exists have been overlooked in the recent handook of combinatorial designs. There are four additional odd n (=191, 5767,7081,8249) in that range for which Hadamard matrices of order 4n exist but are not mentioned in the handbook. There is a unique equivalence class of near-normal sequences NN(36), and the same is true for NN(38) and NN(40). This means that the Yang conjecture on the existence of near-normal sequences NN(n) has been verified for all even n <= 40, but it still remains open.