A187987 Number of nondecreasing arrangements of n numbers x(i) in -(n+6)..(n+6) with the sum of sign(x(i))*2^|x(i)| zero

0, 8, 17, 72, 267, 915, 3407, 12148, 43820, 158361, 570132, 2058621, 7429283, 26823311, 96904923, 350182773, 1266059030, 4579170527, 16568732508, 59974168593, 217170088270, 786671363225, 2850611975840, 10333040668513, 37467797814236, 135900958160905

Offset

1,2

Comments

Column 8 of A187988

Links

Table of n, a(n) for n=1..26.

Example

Some solutions for n=3
.-1...-7...-4...-7...-8...-3...-3...-5...-6...-6...-8...-5...-4...-2...-9...-1
..0....6...-4...-7...-8...-3....2...-5...-6....5....7....4....3...-2....8...-1
..0....6....5....8....9....4....2....6....7....5....7....4....3....3....8....2

Crossrefs

Sequence in context: A097058 A186255 A244792 * A228684 A171065 A134790

Adjacent sequences: A187984 A187985 A187986 * A187988 A187989 A187990

Keyword

nonn

Author

R. H. Hardin Mar 18 2011

Extensions

Terms beyond a(11) from R. J. Mathar, May 17 2023

Status

approved