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A263625
Number of Seidel matrices of order 2n for which Cameron's first cohomology invariant is nonzero.
0
0, 0, 2, 21, 392, 15274
OFFSET
1,3
LINKS
G. Greaves, J. H. Koolen, A. Munemasa, and F. Szöllősi, Equiangular lines in Euclidean spaces, arXiv:1403.2155 [math.CO], 2014-2015.
G. Greaves, J. H. Koolen, A. Munemasa, and F. Szöllősi, Equiangular lines in Euclidean spaces, Journal of Combinatorial Theory, Series A, 138 (2016), 208-235.
CROSSREFS
Sequence in context: A098344 A228384 A216281 * A245686 A091315 A359716
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Oct 24 2015
STATUS
approved