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 A030790 #4 Mar 30 2012 18:56:19 %S A030790 2,3,5,1,11,13,19,22,30,36,58,39,59,50,74,90,62,150,77,132,151,94,177, %T A030790 152,113,178,133,209,155,270,240,181,381,273,308,210,346,384,473,241, %U A030790 428,386,274,430,431,310,755,580,348,479,694,388 %N A030790 a(n)=least k such that s(k)=n, where s=A030787. %K A030790 nonn %O A030790 1,1 %A A030790 _Clark Kimberling_