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%I #12 Dec 17 2022 15:20:20
%S 7,59,163,929,977,1373,1549,1619,1913,2113,2593,4397,5417,5651,6397,
%T 6659,6833,7351,7793,7883,8641,9719,10091,10477,10949,11243,12239,
%U 13441,13457,13691,14753,15349,15467,15971,17747,19051
%N Primes p such that f(f(p)) is prime where f(x) = x^8 + 1.
%F a(n) = (A235983(n)-1)^(1/8).
%e 1619 is prime and (1619^8+1)^8+1 is also prime.
%t Select[Prime[Range[2500]],PrimeQ[(#^8+1)^8+1]&] (* _Harvey P. Dale_, Dec 17 2022 *)
%o (Python)
%o import sympy
%o from sympy import isprime
%o {print(p) for p in range(10**5) if isprime(p) and isprime((p**8+1)**8+1)}
%o (PARI) isok(p) = isprime(p) && (q = p^8+1) && isprime(q^8+1); \\ _Michel Marcus_, Jan 19 2014
%Y Cf. A235983.
%K nonn
%O 1,1
%A _Michel Marcus_ and _Derek Orr_, Jan 19 2014