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A187993 Number of nondecreasing arrangements of n numbers x(i) in -(2n-2)..(2n-2) with the sum of sign(x(i))*x(i)^2 zero. 1
1, 3, 5, 34, 117, 862, 5443, 43750, 354103, 3099873, 27848450, 258912232, 2459308291, 23849609290, 235048481924 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
EXAMPLE
All solutions for n=3
.-1...-2....0...-3...-4
..0....0....0....0....0
..1....2....0....3....4
CROSSREFS
Diagonal of A188002.
Sequence in context: A222484 A354849 A222630 * A221158 A068111 A162444
KEYWORD
nonn,more
AUTHOR
R. H. Hardin, Mar 18 2011
EXTENSIONS
Terms from a(14) on by R. J. Mathar, May 10 2023
STATUS
approved

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Last modified July 14 02:38 EDT 2024. Contains 374291 sequences. (Running on oeis4.)