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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A223613 Numbers k whose abundance is 24: sigma(k) - 2*n = 24. 1
112, 6592, 124672, 33452032, 82364907508 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Suggested by N. J. A. Sloane and Robert G. Wilson v.

a(6) > 10^12.

a(6) > 10^13. - Giovanni Resta, Mar 29 2013

a(6) > 10^18. - Hiroaki Yamanouchi, Aug 23 2018

a(6) <= 36893488040044920832. Every number of the form 2^(j-1)*(2^j - 25), where 2^j - 25 is prime, is a term. - Jon E. Schoenfield, Jun 02 2019

LINKS

Table of n, a(n) for n=1..5.

EXAMPLE

For k = 82364907508, sigma(k) - 2*k = 24.

PROG

(PARI) for(n=1, 10^8, if(sigma(n)-2*n==24, print1(n ", ")))

CROSSREFS

Cf. A000203, A033880.

Sequence in context: A213803 A291214 A035813 * A075910 A089277 A203788

Adjacent sequences:  A223610 A223611 A223612 * A223614 A223615 A223616

KEYWORD

nonn,more

AUTHOR

Donovan Johnson, Mar 23 2013

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 October 15 15:14 EDT 2019. Contains 328030 sequences. (Running on oeis4.)