login
This site is supported by donations to The OEIS Foundation.

 

Logo

The OEIS is looking to hire part-time people to help edit core sequences, upload scanned documents, process citations, fix broken links, etc. - Neil Sloane, njasloane@gmail.com

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A007906 Number of steps for aliquot sequence for n to converge to 1, or 0 if it never reaches 1. 9
1, 2, 2, 3, 2, 0, 2, 3, 4, 4, 2, 7, 2, 5, 5, 6, 2, 4, 2, 7, 3, 6, 2, 5, 0, 7, 3, 0, 2, 15, 2, 3, 6, 8, 3, 4, 2, 7, 3, 4, 2, 14, 2, 5, 7, 8, 2, 6, 4, 3, 4, 9, 2, 13, 3, 5, 3, 4, 2, 11, 2, 9, 3, 4, 3, 12, 2, 5, 4, 6, 2, 9, 2, 5, 5, 5, 3, 11, 2, 7, 5, 6, 2, 6, 3, 9, 7, 7, 2, 10, 4, 6, 4, 4, 0, 9, 2, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Length of transient part of trajectory of n if trajectory reaches 1, otherwise a(n) = 0. See A098008 for a better version. See A098007 for further information.

REFERENCES

R. K. Guy, Unsolved Problems in Number Theory, B6.

R. K. Guy and J. L. Selfridge, Interim report on aliquot series, pp. 557-580 of Proceedings Manitoba Conference on Numerical Mathematics. University of Manitoba, Winnipeg, Oct 1971.

LINKS

Table of n, a(n) for n=1..98.

CROSSREFS

Cf. A098008, A098007, A044050, A003023.

Sequence in context: A173160 A022461 A271226 * A098008 A234808 A248079

Adjacent sequences:  A007903 A007904 A007905 * A007907 A007908 A007909

KEYWORD

nonn

AUTHOR

Michael Gerenrot (sch116(AT)yahoo.com)

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified May 28 21:38 EDT 2017. Contains 287241 sequences.