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!)
A153077 Largest number m such that sigma(m) = A002110(n) where A002110(n) is the product of the first n primes. 3
5, 29, 116, 2309, 30029, 272264, 6715161, 154448901, 3696967556, 126321788241, 5984466237725, 304250263527209, 7475863618097156, 495878856926202725, 17521052944725830450, 1749278213298193453469, 65483587607609351045025 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,1
LINKS
Ray Chandler, Max Alekseyev, Table of n, a(n) for n = 2..24
Max A. Alekseyev, Computing the Inverses, their Power Sums, and Extrema for Euler's Totient and Other Multiplicative Functions. Journal of Integer Sequences, Vol. 19 (2016), Article 16.5.2
FORMULA
a(n) = A057637(A002110(n)). - Chandler
a(A057704(n)) = A002110(A057704(n)) - 1. - Ray Chandler
EXAMPLE
a(9) = 154448901. Sigma(154448901) = A002110(9) = 223092870 = 2*3*5*7*11*13*17*19*23.
CROSSREFS
Sequence in context: A268929 A268244 A297632 * A000352 A327133 A267921
KEYWORD
nonn
AUTHOR
Donovan Johnson, Dec 19 2008
EXTENSIONS
Extended by Ray Chandler, Dec 28 2008
Terms a(22)-a(24) in b-file from Max Alekseyev, Jan 29 2012
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 April 16 03:28 EDT 2024. Contains 371696 sequences. (Running on oeis4.)