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

%S 1,1,1,1,1,3,10,21,36,85,291,923,3735,16127,78677,397086,2338305,

%T 14669249,110594974,880940226,8350924404,83469619311,977221485292,

%U 12070642055579

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

%e Maximal 8 X 8 example

%e .0.0.0.1.1.1.0.0

%e .0.0.0.0.1.0.0.0

%e .1.0.0.0.1.0.0.0

%e .1.1.1.0.0.0.0.1

%e .1.0.0.0.0.1.1.1

%e .0.0.0.1.0.0.0.1

%e .0.0.0.1.0.0.0.0

%e .0.0.1.1.1.0.0.0

%K nonn

%O 1,6

%A _R. H. Hardin_, Oct 26 2008