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Numbers n such that 35^n + 2 is prime.
2

%I #36 Sep 08 2022 08:46:10

%S 0,1,15,83,1457,3959,5351,5355,41359,50327,54435

%N Numbers n such that 35^n + 2 is prime.

%C After 0, all terms are odd. - _Bruno Berselli_, Oct 01 2014

%C a(12) > 2*10^5. - _Robert Price_, Mar 21 2015

%H Henri & Renaud Lifchitz, <a href="http://www.primenumbers.net/prptop/searchform.php?form=35%5En%2B2&amp;action=Search">PRP Top Records, Search for 35^n+2</a>.

%p A247958:=n->`if`(isprime(35^n+2),n,NULL): seq(A247958(n), n=0..1000); # _Wesley Ivan Hurt_, Sep 30 2014

%t Select[Range[0, 10000], PrimeQ[35^# + 2] &]

%o (Magma) [n: n in [0..1000]| IsPrime(35^n+2)];

%o (PARI) is(n)=ispseudoprime(35^n+2) \\ _Charles R Greathouse IV_, Jun 13 2017

%Y Cf. similar sequences listed in A247957.

%K nonn,more

%O 1,3

%A _Vincenzo Librandi_, Sep 28 2014

%E a(9)-a(11) from _Robert Price_, Mar 21 2015