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%I #35 Apr 03 2023 10:36:12
%S 0,3,29,83,153,327,753,879,3333,36977
%N Numbers n such that 2*71^n + 1 is prime.
%C a(11) > 10^5. - _Robert Price_, Jan 12 2016
%H Chris K. Caldwell, The List of Largest Known Primes, <a href="https://t5k.org/primes/page.php?id=38525">2 * 71^879 + 1</a>
%H Chris K. Caldwell, The List of Largest Known Primes, <a href="https://t5k.org/primes/page.php?id=22444">2 * 71^3333 + 1</a>
%H Chris K. Caldwell, The List of Largest Known Primes, <a href="https://t5k.org/primes/page.php?id=67168">2 * 71^36977 + 1</a>
%t Select[Range[0, 10^3], PrimeQ[2*71^# + 1] &] (* _Arkadiusz Wesolowski_, Jul 29 2011 *)
%o (Magma) [n : n in [0..10^3] | IsPrime(2*71^n+1)]; // _Arkadiusz Wesolowski_, Jul 29 2011
%o (PARI) for(n=0, 10^3, if(isprime(2*71^n+1), print1(n, ", "))) \\ _Arkadiusz Wesolowski_, Jul 29 2011
%Y Cf. A141774, A141798.
%K nonn,hard,more
%O 1,2
%A _Arkadiusz Wesolowski_, May 24 2011