%I
%S 3,15,39,135,495,1647,5751,20223,70119,244863,855927,2985903,10426887,
%T 36416223,127148535,444006927,1550518119,5414352255,18907098327,
%U 66024403695,230558764743,805118884191,2811503074743,9817858453455
%N Number of n X 2 0..2 arrays with every element equal to either the sum mod 3 of its vertical neighbors or the sum mod 3 of its horizontal neighbors.
%C Column 2 of A183483.
%H R. H. Hardin, <a href="/A183476/b183476.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 3*a(n1) + 12*a(n3)  18*a(n4)  36*a(n6).
%F Empirical g.f.: 3*x*(1 + 2*x  2*x^2  6*x^3  12*x^4  12*x^5) / ((1  6*x^3)*(1  3*x  6*x^3)).  _Colin Barker_, Mar 29 2018
%e Some solutions for 4 X 2.
%e ..2..2....2..2....1..1....0..0....2..2....0..0....0..0....2..2....0..0....1..1
%e ..0..0....2..2....0..2....0..0....1..1....1..1....2..0....0..0....2..2....1..1
%e ..1..1....0..0....2..1....1..1....0..0....1..1....2..0....2..2....1..1....2..2
%e ..0..0....1..1....2..2....0..0....2..2....1..1....0..0....2..2....1..1....0..0
%Y Cf. A183483.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 05 2011
