A128453 - OEIS

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A128453

Numbers k such that absolute value of 13^k - k^13 is prime.

%I #17 Apr 18 2019 02:55:18

%S 6,12,38,2540

%N Numbers k such that absolute value of 13^k - k^13 is prime.

%C a(5) > 10^5. - _Robert Price_, Apr 17 2019

%t Do[If[PrimeQ[13^n - n^13], Print[n]], {n, 10^4}] (* _Ryan Propper_, Jul 01 2007 *)

%o (PARI) is(n)=ispseudoprime(abs(13^n-n^13)) \\ _Charles R Greathouse IV_, Feb 17 2017

%K hard,more,nonn,less

%O 1,1

%A _Alexander Adamchuk_, Mar 03 2007

%E a(4) from _Ryan Propper_, Jul 01 2007