A147254 - OEIS

A147254

Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 11100-00100-00111 pattern in any orientation.

%I #4 Mar 31 2012 12:35:16

%S 1,1,1,1,5,5,21,29,145,485,3243,11105,102013,454621,6519613,40834561,

%T 722449417

%N Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 11100-00100-00111 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.0.0.0.0.0.0.0

%e .0.0.0.0.0.0.0.1

%e .0.0.1.0.0.0.0.1

%e .0.0.1.0.0.1.1.1

%e .1.1.1.0.0.1.0.0

%e .1.0.0.0.0.1.0.0

%e .1.0.0.0.0.0.0.0

%e .0.0.0.0.0.0.0.0

%K nonn

%O 1,5

%A _R. H. Hardin_, Nov 04 2008