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 A357056 #27 Sep 17 2024 14:17:04 %S A357056 0,1,2,3,4,9,10,13,15,24 %N A357056 Integers k such that k^k + k^2 + 2*k + 1 is prime. %C A357056 The next prime (if any) is unknown, but it must exceed 2000^2000 + 2000^2 + 2*2000 + 1 (a 6603-digit number). %C A357056 a(11) > 15000, if it exists. - _Michael S. Branicky_, Sep 17 2024 %e A357056 If k = 2, then k^k + k^2 + k*2 + 1 = 2^2 + 2^2 + 2*2 + 1 = 13, which is prime. %Y A357056 Cf. A058912, A187605, A231712. %K A357056 nonn,more,hard %O A357056 1,3 %A A357056 _Marco Ripà_, Sep 10 2022