This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A384456 #17 Jun 03 2025 04:54:43 %S A384456 1,2,4,8,16,40 %N A384456 Positive integers k such that (2^k - 1)^k + 2 is prime. %C A384456 If it exists, a(7) > 800. - _Hugo Pfoertner_, Jun 03 2025 %t A384456 Select[Range[100],PrimeQ[(2^#-1)^#+2] &] (* _Stefano Spezia_, Jun 01 2025 *) %o A384456 (PARI) isok(k) = ispseudoprime((2^k - 1)^k + 2); \\ _Michel Marcus_, May 30 2025 %Y A384456 Cf. A019434. %K A384456 nonn,more %O A384456 1,2 %A A384456 _Thomas Ordowski_, May 30 2025