%I A001119
%S A001119 1,1,2,2,16,54
%N A001119 Number of skew-symmetric Hadamard matrices of order 4n.
%D A001119 C. Koukouvinos and S. Stylianou, On skew-Hadamard matrices, Discrete 
               Math., 308 (2008), 2723-2731.
%D A001119 Spence, Edward; Classification of Hadamard matrices of order 24 and 28. 
               Discrete Math. 140 (1995), no. 1-3, 185-243.
%Y A001119 Sequence in context: A076615 A098777 A127226 this_sequence A062282 A012319 
               A012520
%Y A001119 Adjacent sequences: A001116 A001117 A001118 this_sequence A001120 A001121 
               A001122
%K A001119 nonn,hard,nice
%O A001119 2,3
%A A001119 N. J. A. Sloane (njas(AT)research.att.com).