A216423 Numbers k such that 4^k + k^4 + 1 is prime.

0, 6, 12, 3804, 8346, 15528, 147036

Offset: 1

Author

Vincenzo Librandi, Sep 07 2012

Keywords

• nonn

Comments

a(8) > 2*10^5. - Robert Price, Apr 29 2014

a(1)-a(3) are trivially prime. a(4)-a(7) are probable primes. - Robert Price, May 07 2014

Crossrefs

Cf. A100357, A215434-A215446, A216375.

Programs

Mathematica

Select[Range[0, 5000], PrimeQ[4^# + #^4 + 1] &]

PARI

is(n)=ispseudoprime(4^n+n^4+1) \\ Charles R Greathouse IV, Jun 06 2017

Extensions

a(5)-a(7) from Robert Price, Apr 29 2014