%N Number of n X n matrices A with 1's on the main diagonal and -1's and 0's elsewhere such that A + A' has only 0's and -1's off the main diagonal and is positive semi-definite.
%C For number of different values of A + A' see A084553.
%Y Cf. A085657, A085658, A080858, A083029, A038379, A127502.
%A _Max Alekseyev_, Jan 16 2007