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%I #7 Feb 02 2019 11:40:50
%S 5,24,128,688,3728,20224,109760,595744,3233600,17551552,95267648,
%T 517101184,2806762496,15234766720,82692468224,448844700928,
%U 2436274668800,13223803801600,71777205266432,389597975982592,2114690622553088
%N Number of 3 X n 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,1) or (-1,-1) and new values introduced in order 0..2.
%H R. H. Hardin, <a href="/A275267/b275267.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) - 2*a(n-2) - 6*a(n-3) for n>4.
%F Empirical g.f.: x*(5 - 6*x - 6*x^2 - 2*x^3) / (1 - 6*x + 2*x^2 + 6*x^3). - _Colin Barker_, Feb 02 2019
%e Some solutions for n=4:
%e ..0..0..1..0. .0..0..1..0. .0..1..1..0. .0..0..1..0. .0..0..0..0
%e ..0..1..1..2. .1..1..1..2. .1..1..0..0. .1..1..1..0. .0..1..2..1
%e ..1..2..2..2. .1..2..2..2. .2..2..2..2. .2..2..2..2. .2..1..2..1
%Y Row 3 of A275266.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jul 21 2016
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