A189958 1/4 the number of arrangements of 9 nonzero numbers x(i) in -n..n with the sum of sign(x(i))*(|x(i)| mod x(i+1)) equal to zero

128, 17888, 393006, 4014514, 23257218, 101599137, 346371666, 1012894742, 2594438857, 6057314932, 12928069327, 26059247016, 49402250718, 89428018287, 155225765626, 260730899098, 422939460592, 669282239159, 1030485287990

Offset

1,1

Comments

Row 8 of A189951

Links

R. H. Hardin, Table of n, a(n) for n = 1..48

Example

Some solutions with n=3
.-3...-2...-3...-3...-2...-2...-1...-3...-2...-3...-3...-3...-2...-2...-3...-1
.-3...-3...-3...-3...-3...-3...-3...-3...-3...-3...-3...-3...-3...-3...-3...-3
..2...-2....1....1....3...-3...-3....1....3....3...-2...-3...-3...-1...-3...-3
..2....2...-1...-2....3....3...-3...-1...-2....2...-2....2...-1...-2....1...-1
..3...-3...-3....3....1...-2....3....1...-2...-2....1....2...-3....1...-1...-1
.-3....2...-1....3...-3....1....1...-2....1....2....3...-1....1....2...-3...-1
.-1....3...-1....1...-2...-1...-1....3...-3....2...-1....2....2...-3....3...-1
..2....1....1....1....2....1....1....2....1...-1...-1...-3....2....3....1....1
.-2...-1...-2....3....3....3....3...-1...-1....2....1....1....3....3....2...-3

Crossrefs

Sequence in context: A144321 A051251 A264346 * A333605 A264189 A264076

Adjacent sequences: A189955 A189956 A189957 * A189959 A189960 A189961

Keyword

nonn

Author

R. H. Hardin May 02 2011

Status

approved