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Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only either as two by three or three by two blocks.
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%I #3 Mar 31 2012 12:35:09

%S 1,1,1,1,1,1,2,2,3,3,6,7,16,23,50,65,176,221,727,1056,3742,5997,23258,

%T 37914,168488,284282,1460179,2612520,15176540,28767703

%N Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only either as two by three or three by two blocks.

%e Maximal 8 X 8 example

%e .0.0.0.1.1.0.0.0

%e .0.0.0.1.1.0.0.0

%e .0.0.0.1.1.0.0.0

%e .1.1.1.0.0.1.1.1

%e .1.1.1.0.0.1.1.1

%e .0.0.0.1.1.0.0.0

%e .0.0.0.1.1.0.0.0

%e .0.0.0.1.1.0.0.0

%K nonn

%O 1,7

%A _R. H. Hardin_, Oct 27 2008