A187985 Number of nondecreasing arrangements of n numbers x(i) in -(n+4)..(n+4) with the sum of sign(x(i))*2^|x(i)| zero

0, 6, 13, 49, 181, 597, 2166, 7592, 26835, 95590, 339475, 1211024, 4324913, 15465952, 55398468, 198646230, 713134270, 2562757415, 9218114300, 33185957425, 119566240848, 431102833455, 1555423251527, 5615525795887, 20285623430206, 73320521305274, 265147098624058, 959309368316993, 3472389521265649

Offset

1,2

Comments

Column 6 of A187988

Links

Table of n, a(n) for n=1..29.

Example

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

Crossrefs

Sequence in context: A247939 A203977 A003757 * A320043 A296619 A064521

Adjacent sequences: A187982 A187983 A187984 * A187986 A187987 A187988

Keyword

nonn

Author

R. H. Hardin Mar 18 2011

Extensions

Terms from a(14) on from R. J. Mathar, May 17 2023

Status

approved