A322301 Primes p such that 5*2^p + 1 is also prime.

3, 7, 13, 127, 3313, 23473, 819739

Offset: 1

Author

Vincenzo Librandi, Dec 19 2018

Keywords

• nonn
• more

Comments

Primes in A002254.

Crossrefs

Cf. A002254, A175172.

Programs

Magma

[p: p in PrimesUpTo (10000) | IsPrime(5*2^p+1)];

Maple

select(p->isprime(p) and isprime(5*2^p+1),[$0..5000]); # Muniru A Asiru, Dec 19 2018

Mathematica

Select[Prime[Range[4000]], PrimeQ[5 2^# + 1] &]