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A057190 Numbers n such that (24^n+1)/25 is a prime. 14
7, 11, 19, 2207, 2477, 4951 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(7) > 10^5. - Robert Price, Jun 04 2013

LINKS

Table of n, a(n) for n=1..6.

H. Dubner and T. Granlund, Primes of the Form (b^n+1)/(b+1), J. Integer Sequences, 3 (2000), #P00.2.7.

H. Lifchitz, Mersenne and Fermat primes field

PROG

(PARI) isok(n) = (denominator(p=(24^n+1)/25)==1) && isprime(p); \\ Michel Marcus, Oct 30 2017

CROSSREFS

Sequence in context: A282037 A050562 A321806 * A106674 A184063 A076854

Adjacent sequences:  A057187 A057188 A057189 * A057191 A057192 A057193

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Sep 15 2000

STATUS

approved

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Last modified December 13 17:17 EST 2019. Contains 329970 sequences. (Running on oeis4.)