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%I #24 Jul 29 2024 07:37:26
%S 1,11,89,201,977,1351,3869,60681
%N Numbers k such that 8^k - k^8 is prime.
%C From the Lifchitz link: 60681 and 85349 are also in this sequence. - _Robert Price_, Mar 27 2019
%H Henri Lifchitz and Renaud Lifchitz, <a href="http://www.primenumbers.net/prptop/searchform.php?form=8%5En-n%5E8&action=Search">PRP Records</a>.
%t 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 *)
%o (PARI) is(n)=isprime(8^n-n^8) \\ _Charles R Greathouse IV_, Feb 17 2017
%Y Cf. A072180, A109387, A117705, A117706, A128447, A128449, A128450, A128451, A122003, A128453, A128454.
%K hard,more,nonn
%O 1,2
%A _Alexander Adamchuk_, Mar 03 2007
%E a(6) and a(7) from _Donovan Johnson_, Feb 26 2008
%E a(8) confirmed (no intervening terms) by _Michael S. Branicky_, Jul 29 2024