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 A057726 #9 Dec 10 2019 16:42:36 %S A057726 5,11,83,6563 %N A057726 Primes of the form 3^(2^n) + 2. %t A057726 Select[3^2^Range[0,10]+2,PrimeQ] (* _Harvey P. Dale_, Dec 10 2019 *) %Y A057726 Cf. A057727. %K A057726 hard,nonn %O A057726 1,1 %A A057726 _G. L. Honaker, Jr._, Oct 28 2000