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 A143575 #6 Apr 15 2020 23:39:04 %S A143575 0,1,4,5,9,10,13,16,17,20,26,29,34,36,37,40,41,45,49,52,53,58,61,64, %T A143575 68,73,74,80,81,82,89,90,97,101,104,106,109,113,116,117,121,122,136, %U A143575 137,144,146,148,149,153,157,160,164,173,178,180,181,193,194,196,197,202 %N A143575 Numbers m such that A143574(m) = m. %C A143575 A000161(a(n)) = 1. %H A143575 R. Zumkeller, <a href="/A143575/b143575.txt">Table of n, a(n) for n = 1..10000</a> %Y A143575 A000548 is a subsequence. %K A143575 nonn %O A143575 1,3 %A A143575 _Reinhard Zumkeller_, Aug 24 2008