login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Please make a donation to keep the OEIS running. We are now in our 56th year. In the past year we added 10000 new sequences and reached almost 9000 citations (which often say "discovered thanks to the OEIS").
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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 1
42, 366, 4150, 48491, 599181, 7737762, 101530262, 1333341624, 17643516841, 235162515839, 3146321736755, 42232649776342, 568807797004946, 7683091138249061, 104022021281511319, 1411291383524511348 (list; graph; refs; listen; history; text; internal format)
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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 3 05:29 EST 2020. Contains 338899 sequences. (Running on oeis4.)