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%I #3 Mar 31 2012 12:35:08
%S 1,2,1,4,4,13,13,58,68,386,540,3520,6019,47375,94643,905453,2187052,
%T 24871767,71992142,980875049,3393779522,55564082030,230467066626,
%U 4514573141799,22448445351838,526789383889476,3136759423470421
%N Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in two by two blocks.
%e Maximal 7 X 7 example
%e .1.1.0.1.1.0.0
%e .1.1.0.1.1.0.0
%e .0.0.0.0.0.1.1
%e .1.1.0.0.0.1.1
%e .1.1.0.0.0.0.0
%e .0.0.1.1.0.1.1
%e .0.0.1.1.0.1.1
%K nonn
%O 1,2
%A _R. H. Hardin_, Oct 22 2008
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