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%I #12 Feb 02 2020 21:36:01
%S 1,2,1,10,7,167,298
%N Number of ACT classes of Butson-type Hadamard matrices of order 2n over 4th roots of unity.
%H P. H. J. Lampio and F. Szollosi, <a href="https://wiki.aalto.fi/display/QCHmatrices/Home">Quaternary complex Hadamard matrices.</a>
%H P. H. J. Lampio, F. Szollosi and Patric R. J. Östergård, <a href="https://doi.org/10.1016/j.disc.2012.10.001">The quaternary complex Hadamard matrices of orders 10, 12, and 14</a>, Discrete Math., 313 (2012), 189-206.
%Y Cf. A219899.
%K nonn,more
%O 1,2
%A _N. J. A. Sloane_, Dec 12 2012