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A183829
Number of (n+1) X 3 0..2 arrays with each element of every 2 X 2 subblock being the sum mod 3 of two others.
1
127, 823, 5323, 35755, 237671, 1598975, 10698847, 71897239, 482007015, 3236765167, 21714088791, 145764796623, 978116447511, 6565074294447, 44057430220231, 295694291697375, 1984444048131639, 13318411681021391
OFFSET
1,1
COMMENTS
Column 2 of A183836.
LINKS
FORMULA
Empirical: a(n) = 8*a(n-1) + 7*a(n-2) - 142*a(n-3) + 246*a(n-4) + 68*a(n-5) - 386*a(n-6) + 176*a(n-7) + 24*a(n-8).
Empirical g.f.: x*(127 - 193*x - 2150*x^2 + 5444*x^3 - 6*x^4 - 7906*x^5 + 4160*x^6 + 552*x^7) / ((1 - x)*(1 - 7*x - 14*x^2 + 128*x^3 - 118*x^4 - 186*x^5 + 200*x^6 + 24*x^7)). - Colin Barker, Apr 05 2018
EXAMPLE
Some solutions for 5 X 3:
..1..1..2....0..1..2....1..2..2....2..1..0....2..2..0....1..0..1....1..0..2
..0..2..1....2..1..0....1..0..1....0..1..2....1..1..1....1..2..1....2..1..2
..2..1..0....0..2..1....1..2..1....2..1..2....2..0..2....1..2..1....2..0..1
..1..2..1....1..2..1....0..1..2....0..1..2....1..2..1....2..0..1....1..1..2
..0..1..0....1..2..0....1..2..0....2..1..2....0..2..0....1..2..2....2..2..1
CROSSREFS
Cf. A183836.
Sequence in context: A204737 A060201 A140630 * A168487 A299057 A299818
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 07 2011
STATUS
approved