A146817 - OEIS

A146817

Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1110-0111 pattern in any orientation.

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

%S 1,1,1,1,1,1,1,1,17,17,65,65,429,429,5631,5631,146823,146823,4351701,

%T 4351701,186793381,186793381

%N Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1110-0111 pattern in any orientation.

%e Maximal 9 X 9 example

%e .0.0.0.0.0.0.0.0.0

%e .1.0.0.0.0.0.0.0.1

%e .1.1.1.0.0.0.1.1.1

%e .0.1.1.1.0.1.1.1.0

%e .0.0.0.0.0.0.0.0.0

%e .0.1.1.1.0.1.1.1.0

%e .1.1.1.0.0.0.1.1.1

%e .1.0.0.0.0.0.0.0.1

%e .0.0.0.0.0.0.0.0.0

%K nonn

%O 1,9

%A _R. H. Hardin_, Nov 04 2008