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Numbers n such that Lucas(prime(prime(n))) is prime, where Lucas(k) = A000032(k).
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%I #17 Oct 30 2016 17:57:44

%S 2,3,4,5,6,20,30,117,136,1616,5313

%N Numbers n such that Lucas(prime(prime(n))) is prime, where Lucas(k) = A000032(k).

%C Indices of prime Lucas numbers are listed in A001606.

%C Numbers n such that Lucas(prime(n)) is prime are listed in A120561.

%C Primes in A120561 are listed in A123677(n) = prime(a(n)).

%F a(n) = pi(A123677(n)).

%F a(n) = pi(pi(A277290(n))). - _Bobby Jacobs_, Oct 30 2016

%Y Cf. A000032, A123677, A120561, A001606, A277290.

%Y Cf. A119984, A122534 (Numbers n such that Fibonacci(prime(prime(n))) is prime).

%K hard,more,nonn

%O 1,1

%A _Alexander Adamchuk_, Oct 05 2006

%E 5313 found by _Henri Lifchitz_, from _Jens Kruse Andersen_, Jul 24 2014