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Numbers n such that n^8-8 is prime.
5

%I #13 Feb 20 2017 14:47:21

%S 3,7,19,39,73,75,101,107,145,147,171,213,235,247,263,285,319,353,359,

%T 369,399,443,445,521,523,557,613,675,693,707,733,781,791,805,815,829,

%U 837,879,927,943,961,999,1033,1097,1103,1109,1129,1137,1141,1155,1157

%N Numbers n such that n^8-8 is prime.

%C Note that all the numbers in this sequence are odd.

%e 3^8-8 = 6553 is prime. Thus, 3 is a member of this sequence.

%t Select[Range[3,1200,2],PrimeQ[#^8-8]&] (* _Harvey P. Dale_, Jun 27 2014 *)

%o (Python)

%o import sympy

%o from sympy import isprime

%o {print(n) for n in range(10**4) if isprime(n**8-8)}

%o (PARI) is(n)=isprime(n^8-8) \\ _Charles R Greathouse IV_, Feb 20 2017

%Y Cf. A028870, A153974, A239413, A239414, A239415, A239417, A239418, A239345.

%K nonn

%O 1,1

%A _Derek Orr_, Mar 17 2014