A189551 Number of arrangements of 8 nonzero numbers x(i) in -n..n with the sum of trunc(x(i)/x(i+1)) equal to zero

0, 7628, 173792, 1526520, 8485264, 33638540, 111406336, 311438060, 777099536, 1756270204, 3735055528, 7288245592, 13670157716, 24530310400, 42135558056, 69657825372, 112605206044, 176212748340, 270847626492, 404983049496

Offset

1,2

Comments

Row 7 of A189545

Links

R. H. Hardin, Table of n, a(n) for n = 1..94

Example

Some solutions for n=5
.-5...-5...-4...-4...-4...-5...-4...-5...-4...-5...-5...-5...-5...-5...-4...-5
.-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5
.-5...-4...-5...-4...-5....1...-4....4...-5....4....5....2....1...-3....1....5
..5....3...-2...-3...-5...-3....5....5....3....1....5....2...-5....2...-5....4
..4....2...-4....4...-4...-1....3...-1....2....5...-2....5...-3...-2...-1....4
.-3...-3....2...-2....2...-1...-1....2...-2...-1....5...-3...-1...-5....1...-1
..3...-4...-2....3....3....3...-5...-5...-2....3....4...-3...-3...-4....2...-2
.-4....2...-3....5...-3...-5...-4...-1....2....2....5...-4....4....3....2...-1

Crossrefs

Sequence in context: A031854 A253041 A068245 * A235907 A252968 A252051

Adjacent sequences: A189548 A189549 A189550 * A189552 A189553 A189554

Keyword

nonn

Author

R. H. Hardin Apr 23 2011

Status

approved