%I #41 Sep 08 2022 08:46:15
%S 3,5,11,17,31,43,139,173,3709,161923
%N Primes p such that p*2^p + p + 2 is also prime.
%C Primes p such that A069229(n)+2 is prime. - _Michel Marcus_, Jan 12 2016
%C a(11) > 612649. - _Robert Price_, May 22 2016
%e p=11: ((2^11)*11)+11+2 = 22541 (is prime).
%t Select[Prime[Range[4000]], PrimeQ[# 2^# + # + 2] &] (* _Vincenzo Librandi_, Jan 19 2016 *)
%o (PARI) lista(nn) = forprime(p=2, nn, if(ispseudoprime(p*2^p + p + 2), print1(p, ", "))); \\ _Altug Alkan_, Jan 12 2016
%o (Magma) [p: p in PrimesUpTo(200) | IsPrime(p*2^p+p+2)]; // _Vincenzo Librandi_, Jan 19 2016
%Y Cf. A069229.
%K nonn,hard,more
%O 1,1
%A _Emre APARI_, Jan 11 2016
%E a(10) from _Giovanni Resta_, Apr 10 2016
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