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 A050017 #6 Aug 06 2021 07:20:44 %S A050017 1,4,20,3,11,19,27,35,2,10,14,18,22,26,30,34,63,5,67,9,71,13,75,17,50, %T A050017 204,21,54,25,383,29,87,33,437,62,37,241,66,566,8,170,70,445,620,12, %U A050017 174,74,424,16,699,49,203,328,428,553,53,82,24,282,382,457,582,28 %N A050017 a(n) = position of n in A050016. %Y A050017 Cf. A050016. %K A050017 nonn,easy %O A050017 1,2 %A A050017 _Clark Kimberling_