%I #7 Oct 26 2018 09:15:06
%S 6,6,216,1014,13254,98304,984150,8368566,77673624,687582150,
%T 6243858486,55924463616,504631320486,4535315519334,40848737643864,
%U 367488643786134,3308125850845350,29769598506080256,267943541451802614
%N Number of (n+1) X (3+1) 0..2 arrays with no element equal to all horizontal neighbors or unequal to all vertical neighbors, and new values 0..2 introduced in row major order.
%H R. H. Hardin, <a href="/A239532/b239532.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 8*a(n-1) + 26*a(n-2) - 166*a(n-3) + 96*a(n-4) + 198*a(n-5) - 81*a(n-6).
%F Empirical g.f.: 6*(1 - 7*x + 2*x^2 + 21*x^3 - 9*x^4) / ((1 + x)*(1 - 9*x)*(1 - 3*x + x^2)*(1 + 3*x - 9*x^2)). - _Colin Barker_, Oct 26 2018
%e Some solutions for n=5:
%e ..0..1..0..2....0..1..0..1....0..1..1..0....0..1..2..0....0..1..2..1
%e ..0..1..0..2....0..1..0..1....0..1..1..0....0..1..2..0....0..1..2..1
%e ..1..0..0..2....0..1..2..1....0..1..2..1....1..0..1..2....2..1..0..1
%e ..1..0..0..2....0..2..2..1....1..2..2..1....1..0..1..2....2..0..0..1
%e ..0..1..1..0....0..2..0..1....1..2..2..1....1..0..2..0....1..0..2..1
%e ..0..1..1..0....0..2..0..1....1..2..2..1....1..0..2..0....1..0..2..1
%Y Column 3 of A239537.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 21 2014