A146387 - OEIS

A146387

Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 0110-1111 pattern in any orientation.

%I #4 Mar 31 2012 12:35:10

%S 1,1,1,1,1,4,7,18,33,62,229,826,2874,11455,45319,227245,1250786,

%T 7902554,51293369,381222454,3041924174,28668489843,286940122325,

%U 3336283386716

%N Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 0110-1111 pattern in any orientation.

%e Maximal 8 X 8 example

%e .0.0.1.1.1.1.0.0

%e .0.0.0.1.1.0.0.0

%e .1.0.0.0.0.0.0.1

%e .1.1.0.0.0.0.1.1

%e .1.0.0.0.0.0.0.1

%e .0.0.0.1.1.0.0.0

%e .0.0.1.1.1.1.0.0

%K nonn

%O 1,6

%A _R. H. Hardin_