A219616 Numbers k such that 5^k + k^4 is prime.

2, 4, 6, 8, 24, 28, 36, 54, 92, 154, 234, 442, 1138, 2408, 58564

Offset

1,1

Links

Table of n, a(n) for n=1..15.

Mathematica

Select[Range[0, 10000, 2], PrimeQ[(5^# + #^4)] &]

Prog

(Magma) /* The code gives only the terms up to 442: */ [n: n in [0..1000 by 2] | IsPrime(5^n + n^4)];
(PARI) is(n)=ispseudoprime(5^n+n^4) \\ Charles R Greathouse IV, Jul 01 2013

Crossrefs

Cf. A182359, A059802.

Sequence in context: A189153 A194393 A119260 * A067732 A334679 A222712

Adjacent sequences: A219613 A219614 A219615 * A219617 A219618 A219619

Keyword

nonn,more

Author

Vincenzo Librandi, Nov 26 2012

Extensions

a(15) from Michael S. Branicky, Oct 09 2024

Status

approved