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A219899
Number of classes of Butson-type Hadamard matrices of order 2n over 4th roots of unity.
1
1, 2, 1, 15, 10, 319, 752
OFFSET
1,2
LINKS
P. H. J. Lampio and F. Szollosi, Quaternary complex Hadamard matrices.
P. H. J. Lampio, F. Szollosi and Patric R. J. Östergård, The quaternary complex Hadamard matrices of orders 10, 12, and 14, Discrete Math., 313 (2012), 189-206.
CROSSREFS
Cf. A219900.
Sequence in context: A346378 A181869 A141510 * A326600 A272304 A266521
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Dec 12 2012
STATUS
approved