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 A258930 #32 Oct 28 2021 12:37:08 %S A258930 3,2,5,9,15,18,23,22,34,36,41,46,55,58,55,66,83,70 %N A258930 Number of n-digit terms in A000230. %H A258930 Thomas R. Nicely, <a href="https://faculty.lynchburg.edu/~nicely/gaps/gaplist.html">First occurrence prime gaps</a> [For local copy see A000101] %Y A258930 Cf. A000230. %K A258930 nonn,base,more %O A258930 1,1 %A A258930 _James G. Merickel_, Jun 15 2015