A367037 Numbers k such that k^3*2^k - 1 is a prime.

2, 8, 31, 79, 661, 769, 1904, 2527, 9032, 15895, 19171

Offset: 1

Author

Juri-Stepan Gerasimov, Nov 02 2023

Keywords

• nonn
• more

Comments

If it exists, a(12) > 100000. - Hugo Pfoertner, Nov 03 2023

Crossrefs

Numbers k such that k^m*2^k - 1 is prime: A000043 (m = 0), A002234 (m = 1), A058781 (m = 2), this sequence (m = 3).

Programs

Magma

[k: k in [1..700] | IsPrime(k^3*2^k-1)];

Mathematica

Select[Range[3000], PrimeQ[#^3*2^# - 1] &] (* Amiram Eldar, Nov 04 2023 *)

Extensions

a(11) from Hugo Pfoertner, Nov 02 2023