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 A030549 #4 Mar 30 2012 18:56:18 %S A030549 7,19,31,43,55,67,68,70,73,76,79,82,86,104,122,140,158,175,176,178, %T A030549 181,184,187,190,194,212,230,248,266,283,284,286,289,292,295,298,302, %U A030549 320,338,356,374,391,392,394,397,400,403,406,410 %N A030549 Position of n-th 0 in A030548. %K A030549 nonn %O A030549 1,1 %A A030549 _Clark Kimberling_