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A187996 Number of nondecreasing arrangements of n numbers x(i) in -(n+1)..(n+1) with the sum of sign(x(i))*x(i)^2 zero 0
1, 4, 5, 25, 64, 286, 1055, 5191, 24135, 122238, 626982, 3324754, 17890884, 98093994, 544680909, 3062711643, 17400096265 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A188002

LINKS

Table of n, a(n) for n=1..17.

EXAMPLE

Some solutions for n=4

.-4...-2...-5...-5...-1...-2...-3...-4...-3...-4...-2...-5...-2...-3...-3...-4

.-4...-2...-3...-1...-1...-1...-1...-3....1...-1....0....0...-2....0...-3....0

..4....2....3....1....1....1....1....0....2....1....0....3...-1....0....3....0

..4....2....5....5....1....2....3....5....2....4....2....4....3....3....3....4

CROSSREFS

Sequence in context: A333321 A047168 A220538 * A144053 A084465 A056200

Adjacent sequences:  A187993 A187994 A187995 * A187997 A187998 A187999

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 18 2011

STATUS

approved

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Last modified December 2 07:02 EST 2021. Contains 349437 sequences. (Running on oeis4.)