%I #3 Mar 30 2012 16:49:02
%S 0,0,1,3,9,35,195,1218,9184,75492,724995,7428905,86414559,1059030297,
%T 14455096201,206132138310,3228219898080,52501425954872,
%U 927663133292361,16944154401198843,333387373140423145,6756756713150677275,146490980301083247291
%N Number of negative terms in a symmetric determinant of order n.
%D L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 260, #12, p_n.
%Y (A002135-A059422)/2. Cf. A059423.
%K nonn
%O 0,4
%A _N. J. A. Sloane_, Jan 30 2001