A187997 - OEIS

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A187997

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

1, 5, 8, 34, 88, 421, 1696, 8373, 40681, 211234, 1111148, 5987390, 32752144, 181900825, 1022304310, 5807285713, 33301251729, 192592146915, 1122301928144, 6585197085192, 38881934489280, 230894913761474, 1378357322150656, 8268192777096128

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

Column 4 of A188002

LINKS

Table of n, a(n) for n=1..24.

EXAMPLE

All solutions for n=3

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

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

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