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Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 01000-11111-00010 pattern in any orientation.
0

%I #4 Mar 31 2012 12:35:14

%S 1,1,1,1,5,9,21,35,177,589,4235,15969,164553,879607,12456629,97189937,

%T 1947709409,20669429409

%N Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 01000-11111-00010 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.1.0.0.0.0.1.0

%e .1.1.0.1.1.1.1.1

%e .0.1.0.0.1.0.0.0

%e .0.1.1.0.0.0.1.0

%e .0.1.0.0.0.1.1.0

%e .0.0.0.1.0.0.1.0

%e .1.1.1.1.1.0.1.1

%e .0.1.0.0.0.0.1.0

%K nonn

%O 1,5

%A _R. H. Hardin_, Nov 04 2008