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Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 110-111-110 pattern in any orientation.
0

%I #4 Mar 31 2012 12:35:09

%S 1,1,1,1,3,9,20,59,238,1339,8950,63227,541368,5931901,82015459,

%T 1400527040,28248253548,677346206953,19987158806408,732068950428064,

%U 33003291678037712,1801673455589720405,118568477345258796542

%N Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 110-111-110 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.0.0.1.1.0.0.0

%e .0.0.1.1.1.0.0.0

%e .0.1.0.1.1.0.0.0

%e .1.1.1.0.0.0.1.1

%e .1.1.1.0.0.1.1.1

%e .0.0.0.0.1.0.1.1

%e .0.0.0.1.1.1.0.0

%e .0.0.0.1.1.1.0.0

%K nonn

%O 1,5

%A _R. H. Hardin_