A188113 Number of strictly increasing arrangements of n nonzero numbers in -(2n-2)..(2n-2) with sum zero

0, 2, 4, 31, 172, 1154, 8044, 58595, 439514, 3379972, 26513202, 211413199, 1709183316, 13981482114, 115537553904, 963234521237, 8093123460146, 68468543003422, 582819983344618, 4988538052577712, 42911585401063684

Offset

1,2

Comments

Diagonal of A188122

Links

R. H. Hardin, Table of n, a(n) for n = 1..32

Example

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

Crossrefs

Sequence in context: A181620 A220283 A339603 * A259115 A051569 A087186

Adjacent sequences: A188110 A188111 A188112 * A188114 A188115 A188116

Keyword

nonn

Author

R. H. Hardin Mar 21 2011

Status

approved