A201878 Number of zero-sum -n..n arrays of 7 elements with first and second differences also in -n..n

21, 345, 2509, 11107, 36569, 99143, 232969, 492307, 958025, 1743993, 3006947, 4955757, 7859017, 12059931, 17987847, 26166137, 37233755, 51958111, 71242519, 96156041, 127946965, 168048881, 218120357, 280058879, 356003167, 448386363

Offset

1,1

Comments

Row 7 of A201873

Links

R. H. Hardin, Table of n, a(n) for n = 1..142

Example

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

Crossrefs

Sequence in context: A295604 A323277 A075921 * A318269 A298229 A298153

Adjacent sequences: A201875 A201876 A201877 * A201879 A201880 A201881

Keyword

nonn

Author

R. H. Hardin Dec 06 2011

Status

approved