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Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 111-110-111 pattern in any orientation.
0

%I #4 Mar 31 2012 12:35:10

%S 1,1,1,1,1,13,49,205,661,1997,13307,88591,614455,6581035,95397503,

%T 1522572859,23440615715,367710019427,8011532526037,207007785752989,

%U 6626542824985383

%N Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 111-110-111 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.0.0.0.0.1.1.1

%e .1.1.1.0.0.0.1.1

%e .1.1.0.0.0.1.1.1

%e .1.1.1.0.0.0.0.0

%e .0.0.0.0.0.1.1.1

%e .1.1.1.0.0.0.1.1

%e .1.1.0.0.0.1.1.1

%e .1.1.1.0.0.0.0.0

%K nonn

%O 1,6

%A _R. H. Hardin_