A190069 Number of arrangements of n+1 nonzero numbers x(i) in -7..7 with the sum of div(x(i),x(i+1)), where div(a,b)=a/b produces the integer quotient implying a nonnegative remainder, equal to zero

42, 366, 4150, 48491, 599181, 7737762, 101530262, 1333341624, 17643516841, 235162515839, 3146321736755, 42232649776342, 568807797004946, 7683091138249061, 104022021281511319, 1411291383524511348

Offset

1,1

Comments

Column 7 of A190071

Links

R. H. Hardin, Table of n, a(n) for n = 1..81

Example

Some solutions for n=4
..5....3...-4...-5....7....3....1....1....5...-3....3....1...-4....2....4....5
.-5....5...-6...-5....3...-2...-3....2...-1...-2...-3...-5...-2...-3....6...-1
.-5...-3...-7...-7...-2...-7...-3....6....3....1....6....3...-7....2...-5...-1
..7...-2....4....7....2...-5...-4....6....6....2....4...-7....6....1...-3...-7
..5....4....5...-6...-3....4....3...-5....1....7....4...-5...-5...-4....5...-3

Crossrefs

Sequence in context: A134386 A200875 A215628 * A105919 A091082 A189496

Adjacent sequences: A190066 A190067 A190068 * A190070 A190071 A190072

Keyword

nonn

Author

R. H. Hardin May 04 2011

Status

approved