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%I #4 Mar 31 2012 12:35:09
%S 1,1,5,17,45,281,4672,78267,1571678,52679419,3071977536,240721783237,
%T 27403978688452,4744390760050525,1239071516389632223
%N Number of n X n binary arrays with all ones connected only in a 110-111-110 pattern in any orientation.
%e Maximal 8 X 8 example
%e .0.1.1.1.0.1.1.1
%e .0.1.1.1.0.1.1.1
%e .0.0.1.0.0.0.1.0
%e .1.1.0.0.0.0.0.0
%e .1.1.1.0.0.0.1.1
%e .1.1.0.1.0.1.1.1
%e .0.0.1.1.1.0.1.1
%e .0.0.1.1.1.0.0.0
%K nonn
%O 1,3
%A _R. H. Hardin_