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Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a zee 1,1 1,2 2,2 2,3 in any orientation.
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%I #3 Mar 31 2012 12:35:08

%S 1,1,1,1,1,3,7,13,37,103,343,1549,7241,37919,236383,1636125,13465687,

%T 128312593,1395150187,17424865195,251739719221,4153202993611,

%U 79756129711801,1753738354816013,44633769685103851,1301658659951823679

%N Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a zee 1,1 1,2 2,2 2,3 in any orientation.

%e Maximal 8 X 8 example

%e .0.0.0.0.0.0.0.0

%e .0.0.0.0.1.1.0.0

%e .0.0.0.1.1.0.1.0

%e .0.0.1.0.0.1.1.0

%e .0.1.1.0.0.1.0.0

%e .0.1.0.1.1.0.0.0

%e .0.0.1.1.0.0.0.0

%e .0.0.0.0.0.0.0.0

%K nonn

%O 1,6

%A _R. H. Hardin_, Oct 25 2008