A202665 Number of -n..n arrays of 5 elements with first through fourth differences also in -n..n.

19, 213, 1101, 3785, 10205, 23425, 47713, 89007, 154971, 255311, 401933, 609517, 895003, 1278825, 1784361, 2438483, 3271643, 4318837, 5618137, 7213161, 9151545, 11485961, 14273951, 17579509, 21470299, 26021835, 31314591, 37435583, 44478011

Offset

1,1

Comments

Row 5 of A202664.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 2*a(n-3) +2*a(n-4) +a(n-5) -4*a(n-7) -3*a(n-8) -4*a(n-9) +2*a(n-11) +5*a(n-12) +5*a(n-13) +2*a(n-14) -4*a(n-16) -3*a(n-17) -4*a(n-18) +a(n-20) +2*a(n-21) +2*a(n-22) -a(n-25).

Example

Some solutions for n=8
.-1....8...-4...-2....7....6...-4...-8...-5....2....2....1....8...-3....8....5
.-6....4...-5....1....6....6...-3...-5....0...-1....5....0....8...-1....6....1
.-6....3...-3...-2....7....7...-2...-3...-1....1....8...-1....7...-2....4....0
.-6....4...-1...-4....7....8...-1....2...-1....2....5...-5....6...-6....3....0
.-8....0....5...-4....2....5....3....6....6....0...-3...-7....6...-6....3...-1

Crossrefs

Cf. A202664.

Sequence in context: A199132 A201791 A099663 * A115854 A220978 A367980

Adjacent sequences: A202662 A202663 A202664 * A202666 A202667 A202668

Keyword

nonn

Author

R. H. Hardin, Dec 22 2011

Status

approved