A145944 - OEIS

A145944

Number of n X n binary arrays symmetric under horizontal reflection with all ones connected in a 3X2 elbow 1,1 1,2 1,3 2,3 in any orientation.

%I #3 Mar 31 2012 12:35:08

%S 1,1,1,1,13,19,595,1473,41647,139371,13954303,64086157,18839470495,

%T 119460750005,78516712094765,679135834059151,1132864641733411477,

%U 13390989972487068017,60598468634533341708705,981938713996881194950713

%N Number of n X n binary arrays symmetric under horizontal reflection with all ones connected in a 3X2 elbow 1,1 1,2 1,3 2,3 in any orientation.

%e Maximal 8 X 8 example

%e .1.1.1.0.0.1.1.1

%e .1.0.0.0.0.0.0.1

%e .0.1.1.0.0.1.1.0

%e .1.0.1.0.0.1.0.1

%e .1.1.0.0.0.0.1.1

%e .0.0.1.0.0.1.0.0

%e .1.1.1.0.0.1.1.1

%K nonn

%O 1,5

%A _R. H. Hardin_, Oct 25 2008