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 A143741 #5 Oct 11 2017 06:41:08 %S A143741 72,123,45,33,15,9,4,3,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, %T A143741 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, %U A143741 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 %N A143741 Aliquot sequence starting at 72. %F A143741 a(n+1) = A001065(a(n)). - _R. J. Mathar_, Oct 11 2017 %K A143741 nonn,easy %O A143741 0,1 %A A143741 _N. J. A. Sloane_, Nov 30 2008