A216421 Numbers k such that 13^k + k^13 + 1 is prime.

0, 9, 4371, 7985, 14711

Offset

1,2

Comments

a(6) > 10^5. - Robert Price, Feb 23 2014

Links

Table of n, a(n) for n=1..5.

Mathematica

Select[Range[0, 5000], PrimeQ[13^# + #^13 + 1] &]

Prog

(PARI) is(n)=ispseudoprime(13^n+n^13+1) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Cf. A100357, A215434-A215446, A216375.

Sequence in context: A024126 A163018 A193310 * A323337 A167064 A125541

Adjacent sequences: A216418 A216419 A216420 * A216422 A216423 A216424

Keyword

nonn,hard,more

Author

Vincenzo Librandi, Sep 07 2012

Extensions

a(4)-a(5) from Robert Price, Feb 23 2014

Status

approved