A322302 - OEIS

%I #11 Sep 08 2022 08:46:23

%S 3,5,7,19,43,127,211,15329,28277,3771821

%N Primes p such that 11*2^p + 1 is also prime.

%C Primes in A002261.

%p select(p->isprime(p) and isprime(11*2^p+1),[$1..1000]); # _Muniru A Asiru_, Dec 20 2018

%t Select[Prime[Range[1000]], PrimeQ[11 2^# + 1] &]

%o (Magma) [p: p in PrimesUpTo (6000) | IsPrime(11*2^p+1)];

%o (GAP) Filtered([1..1000], p -> IsPrime(p) and IsPrime(11*2^p+1)); # _Muniru A Asiru_, Dec 20 2018

%Y Cf. A002261, A175172.

%K nonn,more

%O 1,1

%A _Vincenzo Librandi_, Dec 20 2018

%E a(10) from _Joerg Arndt_ Dec 20 2018