login

Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.

Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 0111-1100-0111 pattern in any orientation.
0

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

%S 1,1,1,1,1,5,21,61,266,891,3074,18035,122510,915879,8736750,97430523,

%T 1219777035,17287269221

%N Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 0111-1100-0111 pattern in any orientation.

%e Maximal 8 X 8 example

%e .1.1.1.0.0.0.1.0

%e .0.0.1.1.0.1.1.1

%e .1.1.1.0.0.1.0.1

%e .0.0.0.0.0.1.0.1

%e .1.0.1.0.0.0.0.0

%e .1.0.1.0.0.1.1.1

%e .1.1.1.0.1.1.0.0

%e .0.1.0.0.0.1.1.1

%K nonn

%O 1,6

%A _R. H. Hardin_