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A239503
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Numbers n such that n^8+8 and n^8-8 are prime.
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0
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3, 1515, 1689, 3327, 4461, 4641, 4965, 5043, 5583, 5709, 6183, 7089, 9291, 9369, 9699, 10125, 11109, 14175, 15081, 18393, 20295, 26955, 27009, 27219, 29067, 30513, 30807, 35355, 35889, 36003, 37935, 40107, 43461, 48045, 49005, 51783, 53289, 55527, 58833, 61203
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OFFSET
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1,1
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COMMENTS
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All numbers are congruent to 3 mod 6.
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LINKS
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EXAMPLE
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3^8+8 = 6569 is prime and 3^8-8 = 6553 is prime. Thus, 3 is a member of this sequence.
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MATHEMATICA
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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 *)
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PROG
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(Python)
import sympy
from sympy import isprime
def TwoBoth(x):
..for k in range(10**6):
....if isprime(k**x+x) and isprime(k**x-x):
......print(k)
TwoBoth(8)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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