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 A146539 #4 Mar 30 2012 18:51:59 %S A146539 0,4,7,5,4,4,1,7,1,7,1,1,2,1,1,5,1,7,5,4,4,5,7,4,2,7,4,4,7,1,8 %N A146539 A061045 mod 9. %C A146539 From Humphreys spectrum of hydrogen. %Y A146539 Cf. A146322. %K A146539 nonn %O A146539 0,2 %A A146539 _Paul Curtz_, Oct 31 2008