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%I #23 Sep 30 2024 14:17:12
%S 3,5,23,83,239,66029
%N Primes p such that 2^p + p + 6 is also prime.
%C a(6), if it exists, is greater than 20000. - _Dmitry Kamenetsky_, Feb 06 2009
%C a(7), if it exists, is greater than 300000. - _Michael S. Branicky_, Sep 30 2024
%t Select[Prime[Range[1000]], PrimeQ[(2^# + # + 6)]&] (* _Vincenzo Librandi_, Oct 30 2012 *)
%o (Magma) [p: p in PrimesUpTo(1000)| IsPrime(2^p + p +6)]; // _Vincenzo Librandi_, Oct 30 2012
%K nonn,more
%O 1,1
%A _Vincenzo Librandi_, Jan 27 2009
%E a(5) from _Dmitry Kamenetsky_, Feb 06 2009
%E a(6) from _Michael S. Branicky_, Jan 30 2023