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Number of n X n binary arrays symmetric about both diagonal and antidiagonal 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 1,1,1,1,1,1,1,2,3,6,9,14,23,61,135,392,922,2676,7151,26809,87678,

%T 375597,1374921,6569486,27726558,157145315,778948913,5094691047,

%U 28915328479,216796412908

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

%e Maximal 8 X 8 example

%e .0.0.1.1.1.1.0.0

%e .0.0.1.1.1.1.0.0

%e .1.1.0.0.0.0.1.1

%e .1.1.0.0.0.0.1.1

%e .1.1.0.0.0.0.1.1

%e .1.1.0.0.0.0.1.1

%e .0.0.1.1.1.1.0.0

%e .0.0.1.1.1.1.0.0

%K nonn

%O 1,8

%A _R. H. Hardin_, Nov 04 2008