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 A357612 #89 May 17 2023 08:42:25 %S A357612 1,5,41,202,281,394,1157,1211,1816,9845,19780,50800,98621,101945 %N A357612 Numbers k such that 1 + 2^k*k^3 is prime. %e A357612 1 is in this sequence because 1 + 2^1*1^3 = 5 is prime; %e A357612 5 is in this sequence because 1 + 2^5*5^3 = 4001 is prime. %t A357612 Select[Range[2000], PrimeQ[1 + 2^# * #^3] &] (* _Amiram Eldar_, Nov 17 2022 *) %o A357612 (Magma) [n: n in [1..2000] | IsPrime(1+2^n*n^3)]; %Y A357612 Cf. A000040, A005849, A058780. %K A357612 nonn,more,hard %O A357612 1,2 %A A357612 _Juri-Stepan Gerasimov_, Nov 17 2022 %E A357612 a(11)-a(12) from _Amiram Eldar_, Nov 17 2022 %E A357612 a(13)-a(14) from _Michael S. Branicky_, May 16 2023