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Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-1100-0111 pattern in any orientation.
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%I #4 Mar 31 2012 12:35:11

%S 1,1,1,1,1,1,1,3,9,19,37,103,317,831,2581,12105,62053,307133,1586103,

%T 9856867,66841097,477861431

%N Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-1100-0111 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.1.1.1.0.0.0.0

%e .1.0.0.1.1.0.0.0

%e .1.0.0.1.1.0.0.0

%e .1.1.1.0.0.1.1.0

%e .0.1.1.0.0.1.1.1

%e .0.0.0.1.1.0.0.1

%e .0.0.0.1.1.0.0.1

%e .0.0.0.0.1.1.1.0

%K nonn

%O 1,8

%A _R. H. Hardin_, Nov 04 2008