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%I #16 Nov 05 2023 09:02:16
%S 2,8,31,79,661,769,1904,2527,9032,15895,19171
%N Numbers k such that k^3*2^k - 1 is a prime.
%C If it exists, a(12) > 100000. - _Hugo Pfoertner_, Nov 03 2023
%t Select[Range[3000], PrimeQ[#^3*2^# - 1] &] (* _Amiram Eldar_, Nov 04 2023 *)
%o (Magma) [k: k in [1..700] | IsPrime(k^3*2^k-1)];
%Y Numbers k such that k^m*2^k - 1 is prime: A000043 (m = 0), A002234 (m = 1), A058781 (m = 2), this sequence (m = 3).
%K nonn,more
%O 1,1
%A _Juri-Stepan Gerasimov_, Nov 02 2023
%E a(11) from _Hugo Pfoertner_, Nov 02 2023