%I #4 Mar 31 2012 12:35:15
%S 1,1,1,1,1,3,9,23,55,223,1115,7199,49215,368043,3428835,40706551,
%T 594200493,10158791409,204811760131,4951116757551,144268283766901
%N Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 1000-1000-1111-1000 pattern in any orientation.
%e Maximal 8 X 8 example
%e .0.0.0.0.0.0.0.0
%e .0.0.0.0.0.0.0.0
%e .0.0.0.0.0.0.0.1
%e .0.0.0.0.1.1.1.1
%e .0.0.0.1.0.0.0.1
%e .0.0.0.1.0.0.0.1
%e .0.0.0.1.0.0.0.0
%e .0.0.1.1.1.1.0.0
%K nonn
%O 1,6
%A _R. H. Hardin_, Nov 04 2008
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