A297348 Numbers k such that 12*13^k - 1 is prime.

0, 2, 7, 11, 36, 164, 216, 302, 311, 455, 738, 1107, 2244, 3326, 4878, 8067, 46466

Offset: 1

Author

Tim Johannes Ohrtmann, Feb 15 2018

Keywords

• nonn
• more
• hard

Comments

Williams primes to base 12.

Links

• Steven Harvey, Williams primes
• H. C. Williams, The primality of certain integers of the form 2Ar^n - 1, Acta Arith. 39 (1981), 7-17.

Crossrefs

Cf. A003307, A272057, A046865, A079906, A046866, A268061, A268356, A056725, A046867, A079907, A273523.

Programs

Magma

[n: n in [0..10000] |IsPrime(12*13^n-1)];

Mathematica

Select[Range[0, 10000], PrimeQ[12*13^n-1] &]

PARI

for(n=0, 10000, if(isprime(12*13^n-1), print1(n, ", ")))

Extensions

a(16) from Michael S. Branicky, Sep 14 2022

a(17) from Michael S. Branicky, Nov 12 2024