A187986 Number of nondecreasing arrangements of n numbers x(i) in -(n+5)..(n+5) with the sum of sign(x(i))*2^|x(i)| zero

0, 7, 15, 60, 222, 746, 2742, 9689, 34588, 124062, 443469, 1591177, 5710783, 20514746, 73779819, 265523140, 956384656, 3447285428, 12433999199, 44877035870, 162066465738, 585603996081, 2117103447068, 7657611562951, 27710598382843, 100320181906860, 363337451934873, 1316442508560564

Offset

1,2

Comments

Column 7 of A187988

Links

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

Example

All solutions for n=3
.-8...-1...-3...-6...-2...-4...-7...-7...-4...-2...-5...-5...-3...-1...-6
..7....0...-3....5....1...-4...-7....6....3...-2....4...-5....2...-1...-6
..7....0....4....5....1....5....8....6....3....3....4....6....2....2....7

Crossrefs

Sequence in context: A037376 A141548 A146159 * A039789 A279882 A171064

Adjacent sequences: A187983 A187984 A187985 * A187987 A187988 A187989

Keyword

nonn

Author

R. H. Hardin Mar 18 2011

Extensions

More terms from R. J. Mathar, May 17 2023

Status

approved