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A239415
Numbers n such that n^7-7 is prime.
5
60, 66, 132, 212, 242, 246, 290, 296, 312, 326, 380, 384, 446, 516, 524, 554, 654, 704, 740, 782, 834, 1026, 1086, 1142, 1154, 1172, 1182, 1214, 1424, 1430, 1464, 1482, 1494, 1500, 1524, 1604, 1682, 1686, 1752, 1794, 1796, 1844, 1854, 1940, 1952, 1980, 2000, 2010
OFFSET
1,1
COMMENTS
Note that all the numbers in this sequence are even.
EXAMPLE
60^7-7 = 2799359999993 is prime. Thus, 60 is a member of this sequence.
MATHEMATICA
Select[Range[2500], PrimeQ[#^7-7]&] (* Harvey P. Dale, Dec 21 2022 *)
PROG
(Python)
import sympy
from sympy import isprime
{print(n) for n in range(10**4) if isprime(n**7-7)}
CROSSREFS
KEYWORD
nonn
AUTHOR
Derek Orr, Mar 17 2014
STATUS
approved