A202510 Number of zero-sum -7..7 arrays of n elements with first through third differences also in -7..7

1, 7, 57, 297, 1785, 11015, 68781, 436919, 2782455, 17852623, 114949893, 742430377, 4811939259, 31282061157, 203951966061, 1333111663347, 8732654184777, 57311401737559, 376739449264935, 2480070264283519, 16347300910687523

Offset

1,2

Comments

Column 7 of A202511

Links

R. H. Hardin, Table of n, a(n) for n = 1..100

Example

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

Crossrefs

Sequence in context: A274721 A180817 A201438 * A042187 A201872 A218587

Adjacent sequences: A202507 A202508 A202509 * A202511 A202512 A202513

Keyword

nonn

Author

R. H. Hardin Dec 20 2011

Status

approved