cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A123678 Numbers n such that Lucas(prime(prime(n))) is prime, where Lucas(k) = A000032(k).

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%I A123678 #17 Oct 30 2016 17:57:44
%S A123678 2,3,4,5,6,20,30,117,136,1616,5313
%N A123678 Numbers n such that Lucas(prime(prime(n))) is prime, where Lucas(k) = A000032(k).
%C A123678 Indices of prime Lucas numbers are listed in A001606.
%C A123678 Numbers n such that Lucas(prime(n)) is prime are listed in A120561.
%C A123678 Primes in A120561 are listed in A123677(n) = prime(a(n)).
%F A123678 a(n) = pi(A123677(n)).
%F A123678 a(n) = pi(pi(A277290(n))). - _Bobby Jacobs_, Oct 30 2016
%Y A123678 Cf. A000032, A123677, A120561, A001606, A277290.
%Y A123678 Cf. A119984, A122534 (Numbers n such that Fibonacci(prime(prime(n))) is prime).
%K A123678 hard,more,nonn
%O A123678 1,1
%A A123678 _Alexander Adamchuk_, Oct 05 2006
%E A123678 5313 found by _Henri Lifchitz_, from _Jens Kruse Andersen_, Jul 24 2014