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%I #3 Mar 31 2012 12:35:09
%S 1,1,1,1,5,21,83,385,2131,24025,318135,5078109,98561015,2403657061,
%T 86079554793,4029871316637,240018399697859,18147620162041911,
%U 1762019890516576641,229246937643264356069,39291648711744977550585
%N Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 2X4 tee 1,1 1,2 1,3 2,3 1,4 in any orientation.
%e Maximal 8 X 8 example
%e .0.1.1.1.1.0.0.0
%e .1.0.1.0.0.0.0.0
%e .1.1.0.1.1.1.1.0
%e .1.0.1.0.1.0.0.1
%e .1.0.1.1.0.0.0.1
%e .0.0.1.0.0.0.1.1
%e .0.0.1.0.0.1.0.1
%e .0.0.0.1.1.1.1.0
%K nonn
%O 1,5
%A _R. H. Hardin_, Oct 26 2008