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 A008712 #8 Jul 08 2025 01:20:28 %S A008712 10,11,12,13,14,15,16,17,21,23,30,33,120,1111,111111111111111 %N A008712 15 in base 15-n. %K A008712 fini,nonn,base,full %O A008712 0,1 %A A008712 _N. J. A. Sloane_