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Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 3X3 el 1,1 1,2 1,3 2,3 3,3 in any orientation.
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%I #3 Mar 31 2012 12:35:08

%S 1,1,1,1,1,1,11,17,43,77,281,645,3017,9213,61533,218977,1561879,

%T 6900617,60762405,333893691,3718652761,25349082469,352708796463,

%U 2947039725027

%N Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 3X3 el 1,1 1,2 1,3 2,3 3,3 in any orientation.

%e Maximal 8 X 8 example

%e .0.1.0.0.0.0.0.0

%e .0.1.0.0.0.1.1.1

%e .0.1.1.1.0.1.0.0

%e .0.0.0.0.0.1.0.0

%e .0.0.1.0.0.0.0.0

%e .0.0.1.0.1.1.1.0

%e .1.1.1.0.0.0.1.0

%e .0.0.0.0.0.0.1.0

%K nonn

%O 1,7

%A _R. H. Hardin_, Oct 26 2008