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%I #6 Mar 31 2012 12:35:59
%S 1260,16140,201543,2563542,32546547,414199395,5273355420,67176457326,
%T 855995407713,10909479199428,139056001841799,1772599097776482,
%U 22596946895997162,288073093813219107,3672523969509460995
%N 1/6 the number of (n+2)X3 0..2 arrays with each 3X3 subblock containing two of one value, three of another, and four of the last
%C Column 1 of A184407
%H R. H. Hardin, <a href="/A184404/b184404.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n)=3*a(n-1)+87*a(n-2)+951*a(n-3)-378*a(n-4)-56196*a(n-5)-183789*a(n-6)-325296*a(n-7)-124173*a(n-8)+4381533*a(n-9)+8037954*a(n-10)+6954660*a(n-11)-19420560*a(n-12)+2834352*a(n-13)+9447840*a(n-14)+11337408*a(n-15)
%e Some solutions with a(1,1)=0 for 4X3
%e ..0..1..2....0..0..2....0..1..1....0..1..2....0..0..0....0..0..2....0..0..2
%e ..0..0..2....0..2..2....0..1..0....1..0..0....1..2..1....0..2..1....2..2..0
%e ..2..0..1....1..1..2....2..0..2....0..2..1....2..0..1....2..2..1....0..1..1
%e ..0..2..1....0..1..1....1..1..1....2..1..1....2..2..0....0..0..2....2..2..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 12 2011