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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
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OFFSET
1,2
LINKS
Table of n, a(n) for n=1..7.
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
Adjacent sequences:
A219896
A219897
A219898
*
A219900
A219901
A219902
KEYWORD
nonn
,
more
AUTHOR
N. J. A. Sloane
, Dec 12 2012
STATUS
approved
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Last modified July 2 21:16 EDT 2024. Contains 373960 sequences. (Running on oeis4.)