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A219900
Number of ACT classes of Butson-type Hadamard matrices of order 2n over 4th roots of unity.
1
1, 2, 1, 10, 7, 167, 298
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. A219899.
Sequence in context: A081099 A213252 A122017 * A136233 A113088 A060694
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Dec 12 2012
STATUS
approved