A098856 Numbers k such that 4^k*(2^k - 1) + 1 is a prime.

1, 3, 19, 34, 51, 318, 3670, 6348, 33292, 48582, 50235, 50964

Offset: 1

Author

Pierre CAMI, Oct 11 2004

Keywords

• nonn
• more

Comments

a(9) > 11500. - Jinyuan Wang, Mar 19 2020

Crossrefs

Cf. A098857 ((4^k)*(2^k - 1) - 1 is prime).

Programs

Magma

[k: k in [1..500] | IsPrime(4^k*(2^k-1)+1)]; // Jinyuan Wang, Mar 19 2020

Extensions

6348, corresponding to a probable prime, from Ryan Propper, Jun 18 2005

Edited by T. D. Noe, Oct 30 2008

a(9)-a(12) from Michael S. Branicky, Aug 17 2024