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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 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 December 5 21:00 EST 2019. Contains 329779 sequences. (Running on oeis4.)