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A128448
Numbers k such that 8^k - k^8 is prime.
9
1, 11, 89, 201, 977, 1351, 3869, 60681
OFFSET
1,2
COMMENTS
From the Lifchitz link: 60681 and 85349 are also in this sequence. - Robert Price, Mar 27 2019
LINKS
Henri Lifchitz and Renaud Lifchitz, PRP Records.
MATHEMATICA
lst={}; k=8; Do[If[PrimeQ[Abs[k^n-n^k]], AppendTo[lst, n]], {n, 0, 10^4}]; lst (* Vladimir Joseph Stephan Orlovsky, Sep 10 2008 *)
PROG
(PARI) is(n)=isprime(8^n-n^8) \\ Charles R Greathouse IV, Feb 17 2017
KEYWORD
hard,more,nonn
AUTHOR
Alexander Adamchuk, Mar 03 2007
EXTENSIONS
a(6) and a(7) from Donovan Johnson, Feb 26 2008
a(8) confirmed (no intervening terms) by Michael S. Branicky, Jul 29 2024
STATUS
approved