%I #4 Mar 30 2012 17:40:41

%S 1,4,32,592,11904,1192384,134217728

%N Number of real n X n symmetric (+1,-1) matrices with positive permanent.

%Y Cf. A086900, A118994, A118999.

%K nonn,more

%O 1,2

%A _Giovanni Resta_, May 08 2006