A201877 Number of zero-sum -n..n arrays of 6 elements with first and second differences also in -n..n

11, 129, 643, 2191, 5963, 13635, 27647, 51753, 90021, 147955, 233373, 353731, 518711, 742015, 1035117, 1413269, 1897685, 2504735, 3256189, 4183023, 5306711, 6657117, 8276669, 10192753, 12444053, 15087213, 18155235, 21697465, 25786411

Offset

1,1

Comments

Row 6 of A201873

Links

R. H. Hardin, Table of n, a(n) for n = 1..175

Formula

Empirical: a(n) = a(n-3) +a(n-5) +a(n-6) -a(n-8) -a(n-11) +a(n-14) -2*a(n-15) -a(n-17) -a(n-19) +a(n-20) +a(n-22) +a(n-24) +a(n-25) +a(n-27) +a(n-29) -a(n-30) -a(n-32) -2*a(n-34) +a(n-35) -a(n-38) -a(n-41) +a(n-43) +a(n-44) +a(n-46) -a(n-49)

Example

Some solutions for n=9
..6....0...-7....4...-1....4....6...-6....5...-4...-9....6....2....0...-2....4
..4...-3...-1....4....2....2...-2...-5....7....1...-3....2....2....4....1....8
..5....2....2....0....4...-3...-3....1....0...-2....0...-4....0....2....4....3
.-3...-2....4...-2...-1...-1...-1....1...-7....3....7...-5....2...-4....0...-3
.-8....2...-1...-1...-4...-3....0....4...-5...-1....7...-1...-2...-2....2...-4
.-4....1....3...-5....0....1....0....5....0....3...-2....2...-4....0...-5...-8

Crossrefs

Sequence in context: A282042 A015601 A024144 * A015602 A259507 A183837

Adjacent sequences: A201874 A201875 A201876 * A201878 A201879 A201880

Keyword

nonn

Author

R. H. Hardin Dec 06 2011

Status

approved