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 A004694 #11 Oct 26 2023 01:02:38 %S A004694 0,1,1,2,3,5,8,10,18,28,43 %N A004694 Fibonacci numbers written in base 13. (Next term contains a non-decimal character.) %K A004694 nonn,base %O A004694 0,4 %A A004694 _N. J. A. Sloane_