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A210005
Number of (n+1) X 2 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
6, 88, 893, 8217, 73035, 640495, 5586791, 48624987, 422832951, 3675525835, 31945165919, 277628591571, 2412749978775, 20967950350123, 182220740086511, 1583575892972451, 13761939669663303, 119597001511594267
OFFSET
1,1
COMMENTS
Column 1 of A210012.
LINKS
FORMULA
Empirical: a(n) = 11*a(n-1) - 16*a(n-2) - 34*a(n-3) - 12*a(n-4).
Empirical g.f.: x*(3 + 2*x)*(2 + 6*x + 3*x^2) / ((1 - 3*x - 2*x^2)*(1 - 8*x - 6*x^2)). - Colin Barker, Jul 14 2018
EXAMPLE
Some solutions for n=4:
..0..0....0..0....0..1....0..0....0..1....0..0....0..1....0..0....0..1....0..1
..0..1....0..1....2..2....1..2....0..2....0..1....2..0....0..1....0..2....2..0
..0..1....0..1....1..2....2..2....2..0....2..0....1..2....2..0....1..1....0..1
..0..1....2..1....0..2....1..2....0..2....1..2....2..0....1..0....1..2....2..2
..1..2....2..1....2..2....1..1....1..0....0..2....0..1....0..2....1..1....2..1
CROSSREFS
Cf. A210012.
Sequence in context: A173224 A210012 A226426 * A178296 A122770 A265267
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 16 2012
STATUS
approved