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A057188 Numbers n such that (22^n+1)/23 is a prime. 14
3, 5, 13, 43, 79, 101, 107, 227, 353, 7393, 50287 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Some of the larger terms may only correspond to probable primes.

a(12) > 10^5 - Robert Price, Jun 02 2013

LINKS

Table of n, a(n) for n=1..11.

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=(22^n+1)/23)==1) && isprime(p); \\ Michel Marcus, Oct 30 2017

CROSSREFS

Sequence in context: A259932 A178432 A236068 * A128548 A321358 A113606

Adjacent sequences:  A057185 A057186 A057187 * A057189 A057190 A057191

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Sep 15 2000

EXTENSIONS

a(11) from Robert Price, Jun 02 2013

STATUS

approved

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Last modified July 24 15:05 EDT 2021. Contains 346273 sequences. (Running on oeis4.)