%I #31 Nov 10 2023 11:43:29

%S 3,29,43,83,133,209,271,329,415,727,2437,5673,6879,7813,8125,11931,

%T 29433,29491,38397,91141,99459,110935,127247

%N Numbers k such that k^4*2^k - 1 is a prime.

%t Select[Range[6000], PrimeQ[#^4*2^# - 1] &] (* _Amiram Eldar_, Nov 05 2023 *)

%o (Magma) [k: k in [1..500] | IsPrime(k^4*2^k-1)];

%Y Numbers k such that k^m*2^k - 1 is prime: A000043 (m = 0), A002234 (m = 1), A058781 (m = 2), A367037 (m = 3), this sequence (m = 4).

%K nonn,more

%O 1,1

%A _Juri-Stepan Gerasimov_, Nov 04 2023

%E a(17)-a(18) from _Amiram Eldar_, Nov 05 2023

%E a(19) from _Michael S. Branicky_, Nov 05 2023

%E a(20)-a(23) from _Hugo Pfoertner_, Nov 08 2023, Nov 10 2023