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%I #3 Mar 31 2012 12:35:09
%S 1,1,1,1,3,9,19,69,389,2287,15081,141721,1694175,23795099,418616469,
%T 9434924199,264113682081,9153093458787,397472720900369,
%U 21616544571284115,1466493314737915869,124160358455186794957
%N Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 5-point zee 1,1 2,1 2,2 2,3 3,3 in any orientation.
%e Maximal 8 X 8 example
%e .0.0.1.1.0.1.1.0
%e .0.0.0.1.0.0.1.0
%e .1.0.0.1.1.0.1.1
%e .1.1.1.0.0.1.0.0
%e .0.0.1.0.0.1.1.1
%e .1.0.0.1.1.0.0.1
%e .1.1.1.0.1.0.0.0
%e .0.0.1.0.1.1.0.0
%K nonn
%O 1,5
%A _R. H. Hardin_, Oct 26 2008