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A275560 Number of n X 3 0..2 arrays with no element equal to any value at offset (-2,0) (-1,2) or (0,-2) and new values introduced in order 0..2.

%I A275560 #7 Feb 04 2019 13:58:12
%S A275560 3,36,126,504,1872,7200,27360,104256,397440,1513728,5769216,21980160,
%T A275560 83755008,319131648,1215995904,4633362432,17654611968,67270017024,
%U A275560 256320995328,976668327936,3721430827008,14179888005120,54030086701056
%N A275560 Number of n X 3 0..2 arrays with no element equal to any value at offset (-2,0) (-1,2) or (0,-2) and new values introduced in order 0..2.
%H A275560 R. H. Hardin, <a href="/A275560/b275560.txt">Table of n, a(n) for n = 1..210</a>
%F A275560 Empirical: a(n) = 2*a(n-1) + 8*a(n-2) - 16*a(n-4) for n>5.
%F A275560 Empirical g.f.: 3*x*(1 + 10*x + 10*x^2 - 12*x^3 - 32*x^4) / (1 - 2*x - 8*x^2 + 16*x^4). - _Colin Barker_, Feb 04 2019
%e A275560 Some solutions for n=4:
%e A275560 ..0..1..2. .0..0..1. .0..1..2. .0..1..1. .0..0..1. .0..1..2. .0..1..2
%e A275560 ..1..0..0. .0..1..2. .1..1..0. .2..2..0. .2..1..1. .0..0..1. .0..1..1
%e A275560 ..2..2..1. .1..2..2. .2..2..0. .1..0..2. .2..1..0. .2..2..0. .2..0..1
%e A275560 ..0..1..2. .1..0..0. .2..2..1. .0..1..2. .1..0..2. .1..2..0. .2..0..0
%Y A275560 Column 3 of A275565.
%K A275560 nonn
%O A275560 1,1
%A A275560 _R. H. Hardin_, Aug 01 2016