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A212784
Half the number of 0..n arrays of length 5 with second differences nonzero
1
8, 66, 350, 1134, 3010, 6724, 13544, 24870, 42952, 70060, 109638, 165098, 241342, 343074, 476992, 649304, 868684, 1143156, 1483630, 1900056, 2405958, 3013428, 3738744, 4596484, 5605944, 6784266, 8154174, 9735586, 11554762, 13634780
OFFSET
1,1
COMMENTS
Row 3 of A212782
LINKS
FORMULA
Empirical: a(n) = a(n-1) +2*a(n-2) -2*a(n-4) -4*a(n-5) +a(n-6) +3*a(n-7) +3*a(n-8) +a(n-9) -4*a(n-10) -2*a(n-11) +2*a(n-13) +a(n-14) -a(n-15)
EXAMPLE
Some solutions for n=5
..4....0....0....5....0....3....0....5....1....2....1....2....2....2....2....0
..2....1....2....5....3....2....3....1....3....2....0....3....4....5....5....5
..1....1....2....1....2....4....4....2....2....5....2....1....2....3....0....5
..5....2....3....4....2....3....2....5....0....1....0....5....1....0....0....0
..1....0....3....3....4....4....1....1....3....4....0....4....1....4....5....3
CROSSREFS
Sequence in context: A008893 A168302 A121782 * A121781 A121780 A121779
KEYWORD
nonn
AUTHOR
R. H. Hardin May 27 2012
STATUS
approved