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Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1000-1111-1000 pattern in any orientation.
0

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

%S 1,1,1,1,1,1,5,9,24,33,92,207,751,1987,9135,27247,151575,553091,

%T 3687021,16183258,127736835,672115551,6393532548,40630854716,

%U 467493592708

%N Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1000-1111-1000 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.1.1.1.0.0.0.0

%e .0.0.1.0.0.0.0.1

%e .0.0.1.0.1.1.1.1

%e .0.0.1.0.0.0.0.1

%e .1.0.0.0.0.1.0.0

%e .1.1.1.1.0.1.0.0

%e .1.0.0.0.0.1.0.0

%e .0.0.0.0.1.1.1.0

%K nonn

%O 1,7

%A _R. H. Hardin_