A057183 Numbers n such that (17^n + 1)/18 is a prime.

7, 17, 23, 47, 967, 6653, 8297, 41221, 113621, 233689, 348259

Offset

1,1

Links

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

Paul Bourdelais, A Generalized Repunit Conjecture

J. Brillhart et al., Factorizations of b^n +- 1, Contemporary Mathematics, Vol. 22, Amer. Math. Soc., Providence, RI, 3rd edition, 2002.

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

(Prime95) PRP=1, 17, 348259, 1, 0, 0, "18"

Crossrefs

Sequence in context: A265810 A026349 A346656 * A076293 A227276 A300298

Adjacent sequences: A057180 A057181 A057182 * A057184 A057185 A057186

Keyword

nonn

Author

N. J. A. Sloane, Sep 15 2000

Extensions

a(8)=41221 corresponds to a probable prime discovered by Paul Bourdelais, Mar 18 2010

a(9)=113621 corresponds to a probable prime discovered by Paul Bourdelais, Sep 21 2011

a(10)=233689 corresponds to a probable prime discovered by Paul Bourdelais, Sep 03 2013

a(11)=348259 corresponds to a probable prime discovered by Paul Bourdelais, May 22 2014

Status

approved