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A210006
Number of (n+1) X 3 0..2 arrays containing all values 0..2 with every 2 X 2 subblock having two or three distinct values, and new values 0..2 introduced in row major order.
1
88, 2691, 70923, 1808865, 45763485, 1155440875, 29157605895, 735696878225, 18562285346341, 468338954286595, 11816481504639071, 298136973245043705, 7522175051206144237, 189788991513097693371, 4788490127902930108215
OFFSET
1,1
COMMENTS
Column 2 of A210012.
LINKS
FORMULA
Empirical: a(n) = 30*a(n-1) - 109*a(n-2) - 290*a(n-3) + 96*a(n-4) + 136*a(n-5) - 48*a(n-6).
Empirical g.f.: x*(88 + 51*x - 215*x^2 + 14*x^3 + 84*x^4 - 24*x^5) / ((1 - 6*x - 3*x^2 + 2*x^3)*(1 - 24*x - 32*x^2 + 24*x^3)). - Colin Barker, Jul 14 2018
EXAMPLE
Some solutions for n=4:
..0..0..0....0..1..2....0..1..0....0..0..0....0..1..2....0..1..1....0..0..1
..1..1..0....0..0..1....0..1..1....0..1..0....1..1..2....1..0..0....0..1..0
..2..2..0....2..2..2....1..0..2....1..2..0....1..2..1....1..2..2....2..2..1
..1..0..1....1..2..1....1..2..2....1..2..2....0..1..2....0..0..0....2..0..0
..2..0..2....0..2..2....2..0..2....0..0..1....2..1..2....2..0..2....2..0..1
CROSSREFS
Cf. A210012.
Sequence in context: A245954 A248047 A107422 * A194491 A093288 A017804
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 16 2012
STATUS
approved