A147164 - OEIS

A147164

Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1101-0111 pattern in any orientation.

%I #4 Mar 31 2012 12:35:15

%S 1,1,1,1,1,1,1,1,17,17,57,57,317,317,3151,3151,61021,61021,1767277,

%T 1767277,57009275,57009275

%N Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1000-1101-0111 pattern in any orientation.

%e Maximal 9 X 9 example

%e .0.0.0.0.0.0.0.0.0

%e .0.0.0.1.0.1.0.0.0

%e .1.0.1.1.0.1.1.0.1

%e .1.1.1.0.0.0.1.1.1

%e .0.0.0.0.0.0.0.0.0

%e .1.1.1.0.0.0.1.1.1

%e .1.0.1.1.0.1.1.0.1

%e .0.0.0.1.0.1.0.0.0

%e .0.0.0.0.0.0.0.0.0

%K nonn

%O 1,9

%A _R. H. Hardin_, Nov 04 2008