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%I #8 Oct 29 2018 05:05:23
%S 2,27,461,7980,138562,2406061,41780245,725496762,12597953186,
%T 218758280685,3798647658637,65961955769536,1145402258889550,
%U 19889439592325187,345371946166981361,5997241935624779340
%N Number of n X 3 0..3 arrays with no element equal to a different number of vertical neighbors than horizontal neighbors, with new values 0..3 introduced in row major order.
%H R. H. Hardin, <a href="/A240701/b240701.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 15*a(n-1) + 40*a(n-2) + 22*a(n-3) - 60*a(n-4) - 40*a(n-5) - 21*a(n-6) + 45*a(n-7).
%F Empirical g.f.: x*(2 - 3*x - 24*x^2 - 59*x^3 - 52*x^4 - 11*x^5 + 72*x^6) / ((1 - x)*(1 + x + x^2)*(1 - 15*x - 40*x^2 - 21*x^3 + 45*x^4)). - _Colin Barker_, Oct 29 2018
%e Some solutions for n=4:
%e ..0..1..0....0..1..0....0..1..2....0..1..2....0..1..0....0..1..2....0..1..0
%e ..2..3..1....1..2..3....3..0..3....1..0..3....2..0..2....3..2..1....2..3..1
%e ..0..1..3....0..0..1....1..2..0....2..2..0....0..1..3....2..0..3....0..1..2
%e ..1..0..2....0..0..3....3..1..2....2..2..1....2..3..0....3..1..2....1..2..0
%Y Column 3 of A240706.
%K nonn
%O 1,1
%A _R. H. Hardin_, Apr 10 2014
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