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 A006034 Numbers n such that (17^n-1)/16 is prime. (Formerly M2415) 12
 3, 5, 7, 11, 47, 71, 419, 4799, 35149, 54919, 74509 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS No others for any n less than 8447. - Julien Peter Benney (jpbenney(AT)ftml.net), Aug 15 2004 REFERENCES Ribenboim, Paulo; "The Book Of Prime Number Records"; published 1989 by Springer-Verlag; pages 350-354. N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). LINKS H. Dubner, Generalized repunit primes, Math. Comp., 61 (1993), 927-930. H. Dubner, Generalized repunit primes, Math. Comp., 61 (1993), 927-930. [Annotated scanned copy] H. Lifchitz, Mersenne and Fermat primes field MATHEMATICA lst={}; Do[If[PrimeQ[(17^n-1)/16], Print[n]; AppendTo[lst, n]], {n, 10^5}]; lst (* Vladimir Joseph Stephan Orlovsky, Aug 21 2008 *) PROG (PARI) is(n)=isprime((17^n-1)/16) \\ Charles R Greathouse IV, Apr 28 2015 CROSSREFS Sequence in context: A242944 A137355 A147143 * A288716 A083840 A088051 Adjacent sequences:  A006031 A006032 A006033 * A006035 A006036 A006037 KEYWORD hard,nonn,more AUTHOR EXTENSIONS a(9)=35149 & a(10)=54919 are probable primes discovered by Paul Bourdelais, Mar 08 2010 a(11)=74509 is a probable prime discovered by Paul Bourdelais, Mar 10 2010 STATUS approved

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Last modified December 11 21:20 EST 2019. Contains 329937 sequences. (Running on oeis4.)