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%I #8 Sep 23 2018 09:07:00
%S 0,12,54,432,3108,22428,162504,1175592,8507376,61562808,445491480,
%T 3223753560,23328341064,168813022728,1221597213768,8839956302856,
%U 63969389202792,462907576993032,3349780692313320,24240326242963080
%N Number of n X 2 0..2 arrays x(i,j) with each element horizontally, vertically, diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 3 and at least one element with value (x(i,j)-1) mod 3, and upper left element zero.
%H R. H. Hardin, <a href="/A230920/b230920.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-1) + 14*a(n-2) + 16*a(n-3) - 2*a(n-4) + 4*a(n-5).
%F Empirical g.f.: 6*x^2*(1 - x)*(2 + x) / (1 - 5*x - 14*x^2 - 16*x^3 + 2*x^4 - 4*x^5). - _Colin Barker_, Sep 23 2018
%e Some solutions for n=3:
%e ..0..1....0..0....0..2....0..1....0..0....0..0....0..1....0..1....0..2....0..1
%e ..1..2....2..1....1..2....1..2....1..2....1..2....2..2....2..0....1..0....2..1
%e ..0..1....0..1....0..1....0..2....0..0....0..1....1..0....0..1....0..2....0..2
%Y Column 2 of A230926.
%K nonn
%O 1,2
%A _R. H. Hardin_, Nov 01 2013