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%I #13 Mar 07 2020 18:58:01
%S 3,1515,1689,3327,4461,4641,4965,5043,5583,5709,6183,7089,9291,9369,
%T 9699,10125,11109,14175,15081,18393,20295,26955,27009,27219,29067,
%U 30513,30807,35355,35889,36003,37935,40107,43461,48045,49005,51783,53289,55527,58833,61203
%N Numbers n such that n^8+8 and n^8-8 are prime.
%C All numbers are congruent to 3 mod 6.
%C Intersection of A239345 and A239416.
%e 3^8+8 = 6569 is prime and 3^8-8 = 6553 is prime. Thus, 3 is a member of this sequence.
%t Select[Range[3,62000,6],AllTrue[#^8+{8,-8},PrimeQ]&](* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Mar 07 2020 *)
%o (Python)
%o import sympy
%o from sympy import isprime
%o def TwoBoth(x):
%o ..for k in range(10**6):
%o ....if isprime(k**x+x) and isprime(k**x-x):
%o ......print(k)
%o TwoBoth(8)
%Y Cf. A239345, A239416.
%K nonn
%O 1,1
%A _Derek Orr_, Mar 20 2014
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