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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
0, 7, 15, 60, 222, 746, 2742, 9689, 34588, 124062 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 7 of A187988

LINKS

Table of n, a(n) for n=1..10.

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

STATUS

approved

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Last modified September 18 23:30 EDT 2020. Contains 337175 sequences. (Running on oeis4.)