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A187998 Number of nondecreasing arrangements of n numbers x(i) in -(n+3)..(n+3) with the sum of sign(x(i))*x(i)^2 zero 0
1, 6, 9, 46, 117, 636, 2596, 13343, 66452, 354806, 1898800, 10452050, 58080269, 327389928, 1863061322, 10707246833 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 5 of A188002

LINKS

Table of n, a(n) for n=1..16.

EXAMPLE

All solutions for n=3

..0...-1...-2...-4...-4...-5...-3...-5...-6

..0....0....0....0...-3....0....0....3....0

..0....1....2....4....5....5....3....4....6

CROSSREFS

Sequence in context: A154139 A330983 A299914 * A177181 A126110 A340819

Adjacent sequences:  A187995 A187996 A187997 * A187999 A188000 A188001

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 18 2011

STATUS

approved

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Last modified December 4 04:49 EST 2021. Contains 349469 sequences. (Running on oeis4.)