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%I #5 Mar 31 2012 12:37:32
%S 29,1091,27957,655743,14976529,339125187,7657326365,172736626311,
%T 3895426271881,87837486236459,1980567115521301,44657472344530991,
%U 1006924739685862081,22703839965026573971,511919216667906316429
%N Number of (n+1)X3 0..3 arrays containing all values 0..3 with every 2X2 subblock having one or three distinct values, and new values 0..3 introduced in row major order
%C Column 2 of A210309
%H R. H. Hardin, <a href="/A210303/b210303.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 35*a(n-1) -315*a(n-2) +729*a(n-3) +1132*a(n-4) -3804*a(n-5) +688*a(n-6) +1536*a(n-7)
%e Some solutions for n=4
%e ..0..0..0....0..0..1....0..1..0....0..0..1....0..1..0....0..0..0....0..1..0
%e ..0..0..0....1..2..0....0..2..1....1..2..2....0..2..0....0..0..0....2..0..2
%e ..1..2..1....2..3..2....1..1..3....0..0..1....2..3..2....1..2..3....0..3..0
%e ..0..1..3....0..3..0....2..3..0....0..0..2....1..1..1....0..1..1....1..3..1
%e ..1..3..0....2..0..2....1..1..1....1..2..3....3..0..2....0..2..0....3..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 19 2012