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

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

Offset

1,1

Comments

Primes in A002254.

Links

Table of n, a(n) for n=1..7.

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] &]

Prog

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

Crossrefs

Cf. A002254, A175172.

Sequence in context: A237890 A082718 A221211 * A154821 A353008 A084741

Adjacent sequences: A322298 A322299 A322300 * A322302 A322303 A322304

Keyword

nonn,more

Author

Vincenzo Librandi, Dec 19 2018

Status

approved