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%I #5 Mar 31 2012 12:37:31
%S 10,221,4349,78063,1321270,21511540,341220491,5317431003,81861887256,
%T 1249700319322,18966681171701,286687896928349,4321107835703010,
%U 65001162786442684,976443703757880607,14653948717478775383
%N Number of (n+1)X3 0..3 arrays containing all values 0..3 with every 2X2 subblock having one, two or four distinct values, and new values 0..3 introduced in row major order
%C Column 2 of A210143
%H R. H. Hardin, <a href="/A210137/b210137.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 40*a(n-1) -590*a(n-2) +3962*a(n-3) -11899*a(n-4) +12350*a(n-5) +3806*a(n-6) -12980*a(n-7) +4512*a(n-8) +1056*a(n-9) -256*a(n-10)
%e Some solutions for n=4
%e ..0..1..0....0..0..1....0..1..2....0..1..0....0..0..1....0..1..0....0..0..0
%e ..1..0..0....1..0..0....2..3..0....2..3..2....1..0..0....0..0..1....0..0..0
%e ..0..0..2....0..0..0....0..1..2....0..1..0....2..3..3....0..2..3....1..0..2
%e ..1..0..2....0..1..0....0..1..1....0..1..0....0..1..3....1..3..2....0..1..3
%e ..2..3..1....2..3..2....1..0..0....0..0..1....2..3..3....2..0..1....2..3..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 17 2012