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A123677
Primes p such that Lucas(prime(p)) is prime, where Lucas = A000032.
3
3, 5, 7, 11, 13, 71, 113, 643, 769, 13681, 51929
OFFSET
1,1
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.
FORMULA
a(n) = prime(A123678(n)).
a(n) = pi(A277290(n)). - Bobby Jacobs, Oct 30 2016
KEYWORD
hard,more,nonn
AUTHOR
Alexander Adamchuk, Oct 05 2006
EXTENSIONS
51929 found by Henri Lifchitz, from Jens Kruse Andersen, Jul 24 2014
STATUS
approved