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Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 3X3 plus 2,1 2,2 2,3 1,2 3,2.
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%I #3 Mar 31 2012 12:35:08

%S 1,1,2,3,6,13,41,134,523,2341,13112,85330,657274,5867785,62935391,

%T 796238629,11963244988,210625730574,4398387347279,108485411030401,

%U 3172272297097957,109373622124547205,4459641160503515254

%N Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 3X3 plus 2,1 2,2 2,3 1,2 3,2.

%e Maximal 8 X 8 example

%e .0.0.0.1.0.0.0.0

%e .0.0.1.1.1.0.1.0

%e .0.1.0.1.0.1.1.1

%e .1.1.1.0.1.0.1.0

%e .0.1.0.1.1.1.0.0

%e .0.0.1.0.1.0.1.0

%e .0.1.1.1.0.1.1.1

%e .0.0.1.0.0.0.1.0

%K nonn

%O 1,3

%A _R. H. Hardin_, Oct 26 2008