%I #6 Sep 22 2013 06:24:09
%S 2,6,9,11,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
%T 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
%U 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9
%N Number of normal subgroups of the group of n X n signed permutations matrices (described in sequence A066051).
%C The similar sequence for the "ordinary" symmetric group S_n is 1, 2, 3, 4, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, ...
%F For n>=5 a(n) = 9.
%Y Cf. A066051.
%K nonn
%O 1,1
%A Sharon Sela (sharonsela(AT)hotmail.com), Jan 07 2002