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 A206775 #15 Feb 16 2021 05:46:36 %S A206775 1,4,6,7,11,12,15,17,22,24,28,31,40,42,43,47 %N A206775 Values>0 taken by (-1)*A206774. %Y A206775 Cf. A206774. %K A206775 nonn,base,more %O A206775 1,2 %A A206775 _Benoit Cloitre_, Jan 10 2013