OFFSET
1,1
FORMULA
a(n) = (A235983(n)-1)^(1/8).
EXAMPLE
1619 is prime and (1619^8+1)^8+1 is also prime.
MATHEMATICA
Select[Prime[Range[2500]], PrimeQ[(#^8+1)^8+1]&] (* Harvey P. Dale, Dec 17 2022 *)
PROG
(Python)
import sympy
from sympy import isprime
{print(p) for p in range(10**5) if isprime(p) and isprime((p**8+1)**8+1)}
(PARI) isok(p) = isprime(p) && (q = p^8+1) && isprime(q^8+1); \\ Michel Marcus, Jan 19 2014
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Marcus and Derek Orr, Jan 19 2014
STATUS
approved