A367421 Numbers k such that k^5*2^k + 1 is a prime.

1, 41, 53, 231, 532, 1632, 1642, 9701, 13372, 19613, 25518, 31929, 92476, 97433

Offset: 1

Author

Juri-Stepan Gerasimov, Nov 18 2023

Keywords

• nonn
• more

Crossrefs

Numbers k such that k^m*2^k + 1 is a prime: 0, 1, 2, 4, 8, 16, .. (m = 0), A005849 (m = 1), A058780 (m = 2), A357612 (m = 3), A366422 (m = 4), this sequence (m = 5).

Programs

Magma

[k: k in [1..1000] | IsPrime(k^5*2^k+1)];

Mathematica

Select[Range[2000], PrimeQ[#^5*2^# + 1] &] (* Amiram Eldar, Nov 18 2023 *)

Extensions

a(10)-a(12) from Michael S. Branicky, Nov 18 2023

a(13)-a(14) from Michael S. Branicky, Aug 26 2024