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A057184 Numbers n such that (18^n + 1)/19 is a prime. 15
3, 7, 23, 73, 733, 941, 1097, 1933, 4651, 481147 (list; graph; refs; listen; history; text; internal format)



Table of n, a(n) for n=1..10.

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

Paul Bourdelais,A Generalized Repunit Conjecture


Sequence in context: A191638 A148704 A283109 * A148705 A148706 A148707

Adjacent sequences:  A057181 A057182 A057183 * A057185 A057186 A057187




N. J. A. Sloane, Sep 15 2000


a(10) = 481147 corresponds to a probable prime, which was found using PFGW v3.3.1. - Paul Bourdelais, Jul 27 2011



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Last modified December 12 07:00 EST 2019. Contains 329948 sequences. (Running on oeis4.)