A057916 Numbers k such that 3*5^k + 2 is prime.

0, 1, 4, 5, 6, 10, 18, 30, 34, 53, 256, 304, 309, 400, 468, 766, 1470, 2125, 2238, 2404, 4708, 5884, 6264, 8676

Offset

1,3

Comments

a(25) > 21230. - Jinyuan Wang, Dec 08 2019

Links

Table of n, a(n) for n=1..24.

Mathematica

Do[ If[ PrimeQ[ 3*5^n + 2 ], Print[ n ] ], {n, 0, 2000} ]

Prog

(PARI) is(n)=ispseudoprime(3*5^n+2) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Sequence in context: A079257 A001609 A101590 * A249853 A162415 A007606

Adjacent sequences: A057913 A057914 A057915 * A057917 A057918 A057919

Keyword

nonn,more

Author

Robert G. Wilson v, Nov 16 2000

Extensions

First term 0 inserted by Georg Fischer, Aug 01 2019

a(22)-a(24) from Jinyuan Wang, Dec 08 2019

Status

approved