

A190942


Numbers n such that 2*71^n + 1 is prime.


2




OFFSET

1,2


COMMENTS

a(11) > 10^5.  Robert Price, Jan 12 2016


LINKS

Table of n, a(n) for n=1..10.
Chris K. Caldwell, The List of Largest Known Primes, 2 * 71^879 + 1
Chris K. Caldwell, The List of Largest Known Primes, 2 * 71^3333 + 1
Chris K. Caldwell, The List of Largest Known Primes, 2 * 71^36977 + 1


MATHEMATICA

Select[Range[0, 10^3], PrimeQ[2*71^# + 1] &] (* Arkadiusz Wesolowski, Jul 29 2011 *)


PROG

(MAGMA) [n : n in [0..10^3]  IsPrime(2*71^n+1)]; // Arkadiusz Wesolowski, Jul 29 2011
(PARI) for(n=0, 10^3, if(isprime(2*71^n+1), print1(n, ", "))) \\ Arkadiusz Wesolowski, Jul 29 2011


CROSSREFS

Cf. A141774, A141798.
Sequence in context: A221745 A087210 A288918 * A106943 A281712 A106942
Adjacent sequences: A190939 A190940 A190941 * A190943 A190944 A190945


KEYWORD

nonn,hard,more


AUTHOR

Arkadiusz Wesolowski, May 24 2011


STATUS

approved



