A215443 Numbers k such that 5^k + k^5 - 1 is prime.

1, 3, 9, 13, 27, 225, 505, 1605, 7417, 9193, 9235

Offset

1,2

Comments

a(12) > 2*10^5. - Robert Price, May 24 2014

Links

Table of n, a(n) for n=1..11.

Mathematica

Select[Range[0, 3000], PrimeQ[5^# + #^5 - 1] &]

Prog

(Magma) [n: n in [0..300] | IsPrime(5^n + n^5 - 1)]
(PARI) is(n)=ispseudoprime(5^n+n^5-1) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Cf. A215437.

Sequence in context: A018407 A304350 A305913 * A304664 A068885 A305644

Adjacent sequences: A215440 A215441 A215442 * A215444 A215445 A215446

Keyword

nonn,more

Author

Vincenzo Librandi, Sep 03 2012

Extensions

a(9)-a(11) from Robert Price, May 24 2014

Status

approved