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Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 0100-0100-1111-0010 pattern in any orientation.
0

%I #4 Mar 31 2012 12:35:14

%S 1,1,1,1,1,5,25,85,499,2253,9751,103141,1030207,12930523,188986765,

%T 3964919203,79856104275,2515127447393

%N Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 0100-0100-1111-0010 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.1.0.0.0.0.1.0

%e .0.1.1.1.0.0.1.0

%e .1.1.0.0.1.1.1.1

%e .0.1.0.0.0.1.0.0

%e .0.0.1.0.0.0.1.0

%e .1.1.1.1.0.0.1.1

%e .0.1.0.0.1.1.1.0

%e .0.1.0.0.0.0.1.0

%K nonn

%O 1,6

%A _R. H. Hardin_, Nov 04 2008