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 A121410 #7 Jan 04 2013 15:58:37 %S A121410 1,2,4,5,14,21,31,54,65,69,77,171,205,674,675,705,717,740,782,919, %T A121410 1069,1204,1273 %N A121410 Positions of A121409(n) in A119405. %Y A121410 Cf. A119405, A121409. %K A121410 nonn,more,base %O A121410 1,2 %A A121410 _Zak Seidov_, Jul 28 2006