cp's OEIS Frontend

A237366 Primes p such that f(f(p)) is prime where f(x) = x^2+x+1.

%I A237366 #7 Feb 07 2014 10:27:27
%S A237366 7,19,31,67,127,181,223,241,331,367,409,463,487,673,709,751,811,823,
%T A237366 883,997,1117,1231,1321,1489,1549,1861,1933,2083,2179,2287,2473,2551,
%U A237366 2707,2803,2851,2857,2917,2971,3067,3361,3499,3559,3691,3847,3931
%N A237366 Primes p such that f(f(p)) is prime where f(x) = x^2+x+1.
%e A237366 31 is prime and (31^2+31+1)^2+(31^2+31+1)+1 = 987043 is prime. Thus, 31 is a member of this sequence.
%o A237366 (Python)
%o A237366 import sympy
%o A237366 from sympy import isprime
%o A237366 {print(n) for n in range(10**4) if isprime(n) and isprime((n**2+n+1)**2+(n**2+n+1)+1)}
%o A237366 (PARI)
%o A237366 s=[]; forprime(p=2, 4000, if(isprime(p^4+2*p^3+4*p^2+3*p+3), s=concat(s, p))); s \\ _Colin Barker_, Feb 07 2014
%Y A237366 Cf. A237360, A002383.
%K A237366 nonn
%O A237366 1,1
%A A237366 _Derek Orr_, Feb 06 2014