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%I #4 Mar 31 2012 12:35:16
%S 1,1,1,1,1,1,3,7,15,33,101,381,1709,8457,46629,303839,2310935,
%T 20572541,212895819,2545278493,35199007061
%N Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 10000-11100-00111-00001 pattern in any orientation.
%e Maximal 8 X 8 example
%e .0.0.0.0.0.0.0.0
%e .0.0.0.1.0.0.0.0
%e .0.0.0.1.1.1.0.0
%e .0.1.1.0.0.1.1.1
%e .0.0.1.0.0.0.0.1
%e .0.0.1.1.0.0.0.0
%e .0.0.0.1.0.0.0.0
%e .0.0.0.1.1.0.0.0
%K nonn
%O 1,7
%A _R. H. Hardin_