A188327 Number of nondecreasing arrangements of n nonzero numbers in -(n+1)..(n+1) with sum zero

0, 3, 8, 37, 166, 828, 4238, 22563, 122986, 684809, 3877416, 22270064, 129457176, 760412390, 4507076156, 26926958097, 162005104664, 980816681009, 5971509956366, 36540846282249, 224628865150116, 1386650559443616

Offset

1,2

Comments

Column 3 of A188333

Links

R. H. Hardin, Table of n, a(n) for n = 1..30

Example

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

Crossrefs

Sequence in context: A367640 A111543 A276939 * A024039 A147523 A123981

Adjacent sequences: A188324 A188325 A188326 * A188328 A188329 A188330

Keyword

nonn

Author

R. H. Hardin Mar 28 2011

Status

approved