A248546 Numbers k such that 75^k - 2 is prime.

1, 2, 25, 32, 62, 128, 848, 2091, 2882, 11761, 25915

Offset: 1

Author

Vaclav Kotesovec, Oct 08 2014

Keywords

• nonn
• more

Comments

Dedicated to N. J. A. Sloane for his 75th birthday!

Crossrefs

Cf. A014224, A109080, A090669, A128455, A128457, A128458, A128459, A128460, A376850.

Programs

Magma

[n: n in [0..200] | IsPrime(75^n-2)]; // Vincenzo Librandi, Oct 08 2014

Mathematica

Select[Range[1000],PrimeQ[75^#-2]&]

PARI

is(n)=ispseudoprime(75^n-2) \\ Charles R Greathouse IV, Jun 13 2017

Extensions

a(10) from Michael S. Branicky, Apr 02 2023

a(11) from Michael S. Branicky, Oct 10 2024