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Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1000-1111-0010 pattern in any orientation.
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%I #4 Mar 31 2012 12:35:10

%S 1,1,1,1,1,1,1,3,9,19,33,77,239,919,3879,17353,75579,398897,2332505,

%T 16656293,126029691,1117371931,10274166583

%N Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1000-1111-0010 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.0.0.0.0.1.0.0

%e .0.0.1.1.1.1.0.0

%e .0.1.0.1.0.0.1.1

%e .0.1.1.0.0.0.1.0

%e .0.1.0.0.0.1.1.0

%e .1.1.0.0.1.0.1.0

%e .0.0.1.1.1.1.0.0

%e .0.0.1.0.0.0.0.0

%K nonn

%O 1,8

%A _R. H. Hardin_