A198283 - OEIS

%I #5 Mar 31 2012 12:36:34

%S 16,700,31718,1478756,70004726,3337609528,158791292898,7572454386112,

%T 361223237102398,17233549055351780,822235886561754748,

%U 39230600563964575264,1871782716035228820002,89307446755046275015160

%N Number of 2nX12 0..2 arrays with values 0..2 introduced in row major order and each element equal to exactly two horizontal and vertical neighbors

%C Column 6 of A198285

%H R. H. Hardin, <a href="/A198283/b198283.txt">Table of n, a(n) for n = 1..20</a>

%e Some solutions for n=3

%e ..0..0..0..0..0..0..1..1..1..1..1..1....0..0..1..1..1..1..1..1..1..1..0..0

%e ..0..1..1..1..1..0..1..0..0..2..2..1....0..0..1..2..2..0..0..2..2..1..0..0

%e ..0..1..2..2..1..0..1..0..0..2..2..1....2..2..1..2..2..0..0..2..2..1..2..2

%e ..0..1..2..2..1..0..1..2..2..1..1..1....2..2..1..1..1..2..2..1..1..1..2..2

%e ..0..1..1..1..1..0..1..2..2..1..0..0....1..1..2..2..1..2..2..1..2..2..1..1

%e ..0..0..0..0..0..0..1..1..1..1..0..0....1..1..2..2..1..1..1..1..2..2..1..1

%K nonn

%O 1,1

%A _R. H. Hardin_ Oct 23 2011