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A128454
Numbers k such that the absolute value of 14^k - k^14 is prime.
6
1, 5, 11, 89, 101, 579, 655, 8115
OFFSET
1,2
COMMENTS
a(9) > 50000. - Robert Price, Jun 17 2019
MATHEMATICA
Do[If[PrimeQ[Abs[14^n - n^14]], Print[n]], {n, 10^4}] (* Ryan Propper, Mar 27 2007 *)
PROG
(PARI) is(n)=ispseudoprime(abs(14^n-n^14)) \\ Charles R Greathouse IV, Feb 17 2017
KEYWORD
hard,nonn,more
AUTHOR
Alexander Adamchuk, Mar 03 2007
EXTENSIONS
One more term from Ryan Propper, Mar 27 2007
STATUS
approved