The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A328860 Numbers that are 4-imperfect. 1
993803899780063855042560, 2028353759451110328141864960, 6476620014866676143312363520 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Douglas E. Iannucci, On a variation of perfect numbers, INTEGERS: Electronic Journal of Combinatorial Number Theory, 6 (2006), #A41.
Andrew Lelechenko, 4-imperfect numbers, Apr 19 2014.
Michel Marcus, More 4-imperfect numbers, Nov 07 2017.
Michel Marcus, solveIMP PARI script
Michel Marcus, List of 4-imperfect numbers (including the 2 files above), last edit Jun 2019.
Weiyi Zhou and Long Zhu, On k-imperfect numbers, INTEGERS: Electronic Journal of Combinatorial Number Theory, 9 (2009), #A01.
PROG
(PARI) solveIMP(1, 4, 10^24)
CROSSREFS
Cf. A127724 (k-imperfect), A127725 (2-imperfect), A127726 (3-imperfect).
Cf. A309806 (the k values).
Cf. A206369 (the rho function).
Sequence in context: A003806 A257374 A217422 * A095442 A332605 A130682
KEYWORD
nonn,more,bref
AUTHOR
Michel Marcus, Feb 16 2020
STATUS
approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 13 22:21 EDT 2024. Contains 373391 sequences. (Running on oeis4.)