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Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 110-111-110 pattern in any orientation.
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%I #4 Mar 31 2012 12:35:09

%S 1,1,1,1,1,1,10,5,44,17,490,45,3832,281,72349,4672,1945156,78267,

%T 77811492,1571678,4162726786,52679419,355835905036,3071977536,

%U 44996289731531,240721783237

%N Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 110-111-110 pattern in any orientation.

%e Maximal 8 X 8 example

%e .1.1.0.0.0.0.1.1

%e .1.1.1.0.0.1.1.1

%e .1.1.0.0.0.0.1.1

%e .0.0.0.0.0.0.0.0

%e .0.0.0.0.0.0.0.0

%e .1.1.0.0.0.0.1.1

%e .1.1.1.0.0.1.1.1

%e .1.1.0.0.0.0.1.1

%K nonn

%O 1,7

%A _R. H. Hardin_