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Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 0100-0100-1111-0100 pattern in any orientation.
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%I #4 Mar 31 2012 12:35:14

%S 1,1,1,3,5,9,21,69,305,1333,6087,37147,280959,2501123,26363255,

%T 322801403,4679667007,81403804671,1686900283495,41922642406637,

%U 1239283752468159,43217375654523227,1785265760870915049,87797244145177135687

%N Number of n X n binary arrays symmetric about main diagonal with all ones connected only in a 0100-0100-1111-0100 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.0.1.0.0.0.1.0

%e .0.0.1.0.1.1.1.1

%e .1.1.1.1.0.0.1.0

%e .0.0.1.0.0.0.1.0

%e .0.1.0.0.0.1.0.0

%e .0.1.0.0.1.1.1.1

%e .1.1.1.1.0.1.0.0

%e .0.1.0.0.0.1.0.0

%K nonn

%O 1,4

%A _R. H. Hardin_, Nov 04 2008