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A190942
Numbers n such that 2*71^n + 1 is prime.
2
0, 3, 29, 83, 153, 327, 753, 879, 3333, 36977
OFFSET
1,2
COMMENTS
a(11) > 10^5. - Robert Price, Jan 12 2016
LINKS
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
Sequence in context: A221745 A087210 A288918 * A106943 A281712 A106942
KEYWORD
nonn,hard,more
AUTHOR
STATUS
approved