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A249284
Number of length n+3 0..2 arrays with no four consecutive terms having the sum of any three elements equal to three times the fourth
1
66, 168, 428, 1094, 2792, 7132, 18232, 46616, 119176, 304696, 779066, 1992002, 5093330, 13023126, 33299000, 85142802, 217703012, 556648464, 1423304428, 3639273226, 9305324178, 23792953554, 60836640416, 155554327024, 397739724496
OFFSET
1,1
COMMENTS
Column 2 of A249290
LINKS
FORMULA
Empirical: a(n) = a(n-1) +2*a(n-2) +3*a(n-3) +7*a(n-4) +a(n-5) -6*a(n-6) -12*a(n-7) -14*a(n-8) -14*a(n-9) -7*a(n-10) +3*a(n-11) +2*a(n-12)
EXAMPLE
Some solutions for n=9
..1....0....2....2....1....1....0....1....1....1....0....1....1....2....2....1
..1....0....1....0....0....1....1....0....1....0....0....1....1....0....1....0
..0....1....0....0....2....0....2....2....2....2....0....1....2....0....0....2
..1....0....0....0....2....1....0....2....2....0....2....2....1....0....0....2
..0....1....2....1....0....0....0....0....1....2....2....2....2....1....1....2
..2....0....2....0....0....0....0....1....2....1....0....0....2....0....1....0
..0....1....2....0....0....1....2....0....2....2....2....2....1....0....0....0
..2....1....0....1....1....1....0....1....2....1....0....2....0....1....0....2
..0....0....0....1....2....0....2....0....0....2....2....1....0....0....2....2
..2....0....2....1....2....1....1....0....0....1....1....2....0....2....1....2
..2....0....2....2....1....0....2....0....1....2....2....0....2....0....2....1
..2....2....1....2....2....0....2....1....2....0....1....0....2....0....2....0
CROSSREFS
Sequence in context: A043514 A044398 A044779 * A255102 A202647 A202640
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 24 2014
STATUS
approved