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 A140783 #3 Mar 30 2012 18:51:58 %S A140783 1,2,3,6,9,9,18,18,27,27,27,27,45,45,45,63,54,54,63,72,54,81,99,90,81, %T A140783 90,99,99,99,126,117,135,189,198,171,180,171,180,171,180,189,162,189, %U A140783 207,180,198,207,243,261,243,297,270,243,261,279,288,324,342,315,315 %N A140783 Digit sum of A091137(n). %F A140783 a(n)= A007953(A091137(n)). - _R. J. Mathar_, Jul 29 2008 %K A140783 nonn,base %O A140783 0,2 %A A140783 _Paul Curtz_, Jul 13 2008 %E A140783 Edited and extended by _R. J. Mathar_, Jul 29 2008