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A248437
Number of length 4+2 0..n arrays with every three consecutive terms having the sum of some two elements equal to twice the third
1
2, 9, 28, 101, 198, 327, 462, 691, 932, 1203, 1474, 1829, 2184, 2551, 2954, 3459, 3964, 4501, 5038, 5653, 6286, 6925, 7564, 8327, 9114, 9907, 10712, 11577, 12442, 13363, 14284, 15307, 16342, 17383, 18454, 19609, 20764, 21925, 23098, 24389, 25680, 27009
OFFSET
1,1
COMMENTS
Row 4 of A248433
LINKS
FORMULA
Empirical: a(n) = -a(n-4) +a(n-5) +a(n-7) -a(n-8) +a(n-9) +a(n-11) -a(n-12) +a(n-13) +a(n-15) -a(n-21) -a(n-23) +a(n-24) -a(n-25) -a(n-27) +a(n-28) -a(n-29) -a(n-31) +a(n-32) +a(n-36)
EXAMPLE
Some solutions for n=6
..4....1....3....1....5....3....2....6....5....4....3....2....5....3....5....1
..5....5....4....3....3....1....4....2....4....2....5....1....4....3....1....3
..6....3....2....2....1....2....0....4....6....0....1....3....6....3....3....5
..4....4....3....1....2....0....2....0....2....4....3....2....2....3....5....1
..2....2....1....0....3....4....1....2....4....2....2....4....4....3....4....3
..0....3....5....2....4....2....3....4....0....3....4....3....6....3....6....5
CROSSREFS
Sequence in context: A323957 A026087 A109188 * A002532 A360023 A098518
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 06 2014
STATUS
approved