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!)
A057189 Numbers n such that (23^n+1)/24 is a prime. 14
11, 13, 67, 109, 331, 587, 24071, 29881, 44053 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Some of the larger terms may only correspond to probable primes.
a(10) > 10^5. - Robert Price, Jun 04 2013
LINKS
H. Dubner and T. Granlund, Primes of the Form (b^n+1)/(b+1), J. Integer Sequences, 3 (2000), #P00.2.7.
PROG
(PARI) isok(n) = (denominator(p=(23^n+1)/24)==1) && isprime(p); \\ Michel Marcus, Oct 30 2017
CROSSREFS
Sequence in context: A234799 A036295 A132201 * A072580 A186640 A226242
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Sep 15 2000
EXTENSIONS
a(7)-a(9) from Robert Price, Jun 04 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 19 02:46 EDT 2024. Contains 370952 sequences. (Running on oeis4.)