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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

Table of n, a(n) for n=1..9.

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

Adjacent sequences:  A057186 A057187 A057188 * A057190 A057191 A057192

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Sep 15 2000

EXTENSIONS

a(7)-a(9) from Robert Price, Jun 04 2013

STATUS

approved

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Last modified September 20 17:42 EDT 2021. Contains 347588 sequences. (Running on oeis4.)