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Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1111-1111 pattern in any orientation.
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%I #4 Mar 31 2012 12:35:14

%S 1,1,1,3,5,9,19,60,189,892,3177,18960,89571,754227,4905159,53337014,

%T 466215312,6729449504,78188089715,1533329125669

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

%e Maximal 8 X 8 example

%e .1.1.0.0.1.1.0.0

%e .1.1.0.0.1.1.0.0

%e .1.1.0.0.1.1.0.0

%e .1.1.0.0.1.1.0.0

%e .0.0.1.1.0.0.1.1

%e .0.0.1.1.0.0.1.1

%e .0.0.1.1.0.0.1.1

%e .0.0.1.1.0.0.1.1

%K nonn

%O 1,4

%A _R. H. Hardin_, Nov 04 2008