A202507 Number of zero-sum -4..4 arrays of n elements with first through third differences also in -4..4.

1, 5, 21, 75, 239, 883, 3285, 12619, 48079, 185533, 718529, 2793599, 10889311, 42597829, 167140877, 657518773, 2592183923, 10238899137, 40508826935, 160499036493, 636728024223, 2528978914493, 10055447397817, 40020622051941

Offset

1,2

Comments

Column 4 of A202511.

Links

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

Example

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

Crossrefs

Cf. A202511.

Sequence in context: A186948 A271251 A201435 * A079923 A272452 A271088

Adjacent sequences: A202504 A202505 A202506 * A202508 A202509 A202510

Keyword

nonn

Author

R. H. Hardin, Dec 20 2011

Status

approved