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A188251 Number of arrangements of 5 nonzero numbers x(i) in -n..n with the sum of x(i)*x(i+1) equal to zero 1
12, 120, 548, 1504, 3292, 6376, 10564, 17040, 25436, 36808, 49556, 68912, 87804, 113384, 144644, 180912, 216044, 267160, 312404, 377904, 446588, 519976, 590420, 696576, 791164, 898456, 1016756, 1159280, 1278636, 1460936, 1598916, 1784224 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 3 of A188249

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..47

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Sequence in context: A006953 A164877 A121032 * A093334 A001816 A133386

Adjacent sequences:  A188248 A188249 A188250 * A188252 A188253 A188254

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 25 2011

STATUS

approved

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Last modified October 23 05:56 EDT 2019. Contains 328335 sequences. (Running on oeis4.)