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 A132928 #3 Mar 11 2014 01:34:10 %S A132928 6,628,628496,6284968128,628496812833550336, %T A132928 6284968128335503368589869056, %U A132928 6284968128335503368589869056137438691328,62849681283355033685898690561374386913282305843008139952128 %N A132928 Concatenation of first n perfect numbers. %H A132928 Omar E. Pol, <a href="http://www.polprimos.com">Determinacion geometrica de los numeros primos y perfectos</a>. %Y A132928 Perfect numbers: A000396. Cf. A007908, A019518, A078795. %K A132928 easy,nonn,base %O A132928 1,1 %A A132928 _Omar E. Pol_, Sep 05 2007