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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 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 December 14 22:42 EST 2019. Contains 329987 sequences. (Running on oeis4.)