A086218 Primes p such that 3^p - 2 is prime.

2, 5, 37, 41, 317, 541, 2521

Offset

1,1

Comments

a(8) > 1180181, if it exists (based on the data at A014224). - Amiram Eldar, Jul 07 2024

Links

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

Formula

a(n) = prime(A089919(n)). - Amiram Eldar, Jul 07 2024

Mathematica

f[n_]:=3^n-2; lst={}; Do[p=Prime[n]; If[PrimeQ[f[p]], Print[p]; AppendTo[lst, p]], {n, 7!}]; lst (* Vladimir Joseph Stephan Orlovsky, Jul 17 2009 *)

Crossrefs

Subsequence of prime terms of A014224.

Cf. A086214, A089919.

Sequence in context: A284605 A106129 A163499 * A202637 A138658 A067464

Adjacent sequences: A086215 A086216 A086217 * A086219 A086220 A086221

Keyword

nonn,hard,more

Author

Cino Hilliard, Aug 28 2003

Extensions

a(7) from Jorge Coveiro, Apr 10 2004

Status

approved