A128453 Numbers k such that absolute value of 13^k - k^13 is prime.

6, 12, 38, 2540

Offset: 1

Author

Alexander Adamchuk, Mar 03 2007

Keywords

• hard
• more
• nonn
• less

Comments

a(5) > 10^5. - Robert Price, Apr 17 2019

Programs

Mathematica

Do[If[PrimeQ[13^n - n^13], Print[n]], {n, 10^4}] (* Ryan Propper, Jul 01 2007 *)

PARI

is(n)=ispseudoprime(abs(13^n-n^13)) \\ Charles R Greathouse IV, Feb 17 2017

Extensions

a(4) from Ryan Propper, Jul 01 2007