%I #7 Feb 10 2014 04:27:03
%S 29,197,673,2297,3613,5923,6133,6917,8219,13553,15667,17137,21911,
%T 30941,33587,35407,38053,44017,45557,46663,51241,53453,65731,67187,
%U 82349,94151,115361,132287,143711,164011,164291,165523,178613,180797,182141
%N Primes p such that f(f(p)) is prime where f(x) = Phi_6(x).
%C Phi_k(x) is the k-th cyclotomic polynomial, see A013595 or A013596.
%e 29 is prime and f(29^6+29^5+29^4+29^3+29^2+29+1) = 54672347801779330810964871392077416495507203132755717 is prime. Thus, 29 is a member of this sequence.
%o (Python)
%o import sympy
%o from sympy import isprime
%o {print(n) for n in range(10**6) if isprime(n) and isprime((n**6+n**5+n**4+n**3+n**2+n+1)**6+(n**6+n**5+n**4+n**3+n**2+n+1)**5+(n**6+n**5+n**4+n**3+n**2+n+1)**4+(n**6+n**5+n**4+n**3+n**2+n+1)**3+(n**6+n**5+n**4+n**3+n**2+n+1)**2+(n**6+n**5+n**4+n**3+n**2+n+1)+1)}
%Y Cf. A088550, A237364.
%K nonn
%O 1,1
%A _Derek Orr_, Feb 08 2014