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Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
%I #4 Mar 31 2012 12:35:09
%S 1,1,1,1,1,1,3,3,5,5,9,9,19,19,71,71,265,265,1031,1031,4533,4533,
%T 26975,26975,188011,188011,1487007,1487007,13567107,13567107
%N Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 110-111-011 pattern in any orientation.
%e Maximal 8 X 8 example
%e .1.1.0.0.0.0.1.1
%e .1.1.1.0.0.1.1.1
%e .0.1.1.0.0.1.1.0
%e .0.0.0.0.0.0.0.0
%e .0.0.0.0.0.0.0.0
%e .0.1.1.0.0.1.1.0
%e .1.1.1.0.0.1.1.1
%e .1.1.0.0.0.0.1.1
%K nonn
%O 1,7
%A _R. H. Hardin_