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

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

Offset

1,2

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

Links

Table of n, a(n) for n=1..7.

Mathematica

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

Prog

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

Crossrefs

Cf. A100357, A215434-A215446, A216375.

Sequence in context: A036900 A159282 A202383 * A229336 A363755 A070396

Adjacent sequences: A216420 A216421 A216422 * A216424 A216425 A216426

Keyword

nonn

Author

Vincenzo Librandi, Sep 07 2012

Extensions

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

Status

approved