

A057181


Numbers n such that (15^n + 1)/16 is a prime.


15




OFFSET

1,1


LINKS

Table of n, a(n) for n=1..8.
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, 15, 551927, 1, 0, 0, "16"


CROSSREFS

Sequence in context: A048722 A061955 A113834 * A227077 A136934 A201794
Adjacent sequences: A057178 A057179 A057180 * A057182 A057183 A057184


KEYWORD

nonn


AUTHOR

N. J. A. Sloane, Sep 15 2000


EXTENSIONS

a(6)=54449 is a probable prime discovered by Paul Bourdelais, Mar 15 2010
a(7)=67489 is a probable prime discovered by Paul Bourdelais, Mar 16 2010
a(8)=551927 is a probable prime discovered by Paul Bourdelais, Jul 03 2013


STATUS

approved



