A188324 Number of nondecreasing arrangements of n nonzero numbers in -(2n-2)..(2n-2) with sum zero

0, 2, 8, 61, 472, 4050, 36454, 341988, 3306612, 32757830, 330964946, 3398830478, 35386215292, 372754193214, 3966423984516, 42579631811396, 460648926971334, 5017891492413126, 54996459314116816, 606092251444553993

Offset

1,2

Comments

Diagonal of A188333

Links

R. H. Hardin, Table of n, a(n) for n = 1..24

Example

Some solutions for n=6
.-9...-8...-8...-6...-9...-7..-10..-10..-10...-8...-8...-8...-9...-7...-6...-7
.-1...-1...-6...-2...-5...-7...-7...-2...-2...-7...-7...-4...-6...-7...-5...-6
.-1...-1...-3...-1...-4...-3....1...-2...-2...-2....1...-4...-2...-2...-2....1
..1...-1....4....3....1....5....3...-2....2...-1....2...-4...-2....2...-1....3
..5....2....5....3....8....5....4....8....3....9....3...10....9....6....6....3
..5....9....8....3....9....7....9....8....9....9....9...10...10....8....8....6

Crossrefs

Sequence in context: A321979 A139017 A322012 * A368450 A370913 A208356

Adjacent sequences: A188321 A188322 A188323 * A188325 A188326 A188327

Keyword

nonn

Author

R. H. Hardin Mar 28 2011

Status

approved