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Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 110-111-101 pattern in any orientation.
0

%I #4 Mar 31 2012 12:35:09

%S 1,1,1,1,1,1,9,9,33,33,81,81,609,609,23953,23953,643873,643873,

%T 12050113,12050113,545308145,545308145

%N Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 110-111-101 pattern in any orientation.

%e Maximal 8 X 8 example

%e .1.1.0.0.0.0.1.1

%e .0.1.1.0.0.1.1.0

%e .1.1.1.0.0.1.1.1

%e .0.0.0.0.0.0.0.0

%e .0.0.0.0.0.0.0.0

%e .1.1.1.0.0.1.1.1

%e .0.1.1.0.0.1.1.0

%e .1.1.0.0.0.0.1.1

%K nonn

%O 1,7

%A _R. H. Hardin_