A188118 Number of strictly increasing arrangements of n nonzero numbers in -(n+3)..(n+3) with sum zero

0, 5, 12, 51, 172, 624, 2216, 7970, 28660, 103599, 375854, 1368883, 5003340, 18351050, 67525962, 249235562, 922567826, 3424217898, 12741735980, 47526320684, 177671217830, 665611279282, 2498575823284, 9396889413586

Offset

1,2

Comments

Column 5 of A188122

Links

R. H. Hardin, Table of n, a(n) for n = 1..28

Example

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

Crossrefs

Sequence in context: A135769 A074024 A054661 * A062978 A189421 A066961

Adjacent sequences: A188115 A188116 A188117 * A188119 A188120 A188121

Keyword

nonn

Author

R. H. Hardin Mar 21 2011

Status

approved