A123677 Primes p such that Lucas(prime(p)) is prime, where Lucas = A000032.

3, 5, 7, 11, 13, 71, 113, 643, 769, 13681, 51929

Offset: 1

Author

Alexander Adamchuk, Oct 05 2006

Keywords

• hard
• more
• nonn

Comments

These are the primes in A120561.

Numbers n such that Lucas(prime(n)) is prime are listed in A120561; indices of prime Lucas numbers are listed in A001606.

Crossrefs

Cf. A000032, A123678, A120561, A001606, A119984, A122534, A277290.

Formula

a(n) = prime(A123678(n)).

a(n) = pi(A277290(n)). - Bobby Jacobs, Oct 30 2016

Extensions

51929 found by Henri Lifchitz, from Jens Kruse Andersen, Jul 24 2014