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A189956 1/4 the number of arrangements of 7 nonzero numbers x(i) in -n..n with the sum of sign(x(i))*(|x(i)| mod x(i+1)) equal to zero 1
32, 1152, 13569, 73992, 280284, 839968, 2095080, 4678100, 9483181, 17859030, 31526421, 53335818, 86113621, 134395470, 203331437, 299865250, 431183908, 608327784, 840894817, 1144932377, 1534996553, 2030482093, 2648947079 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 6 of A189951

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..87

EXAMPLE

Some solutions with n=3

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

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

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

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

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

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

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

CROSSREFS

Sequence in context: A038097 A208267 A184758 * A318014 A320400 A194652

Adjacent sequences:  A189953 A189954 A189955 * A189957 A189958 A189959

KEYWORD

nonn

AUTHOR

R. H. Hardin May 02 2011

STATUS

approved

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Last modified October 26 08:00 EDT 2021. Contains 348267 sequences. (Running on oeis4.)