A137652 Numbers k such that 12^k + 5 is prime.

1, 2, 3, 8, 21, 26, 31, 50, 55, 69, 392, 661, 12648

Offset

1,2

Comments

a(14) > 15000. - Jinyuan Wang, Mar 05 2020

Links

Table of n, a(n) for n=1..13.

Mathematica

Do[If[PrimeQ[(12^n+5)], Print[n]], {n, 2000}]

Prog

(PARI) is(n)=ispseudoprime(12^n+5) \\ Charles R Greathouse IV, Jun 06 2017

Crossrefs

Cf. A137653, A137654.

Sequence in context: A175490 A118854 A192151 * A185381 A251608 A288252

Adjacent sequences: A137649 A137650 A137651 * A137653 A137654 A137655

Keyword

nonn,more

Author

Zak Seidov, Feb 01 2008

Extensions

a(13) from Jinyuan Wang, Mar 05 2020

Status

approved