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 A190686 #4 Mar 30 2012 18:57:28 %S A190686 1,2,5,9,13,16,17,20,24,28,31,32,35,39,42,43,46,50,54,57,58,61,65,69, %T A190686 72,73,76,80,84,87,91,95,98,99,102,106,110,113,114,117,121,125,128, %U A190686 129,132,136,139,140,143,147,151,154,155,158,162,166,169,170,173,177,181,184,185,188,192,195,196,199,203,207,210,211,214,218,222 %N A190686 Positions of 2 in A190683. %C A190686 See A190683. %t A190686 (See A190683.) %Y A190686 Cf. A190683. %K A190686 nonn %O A190686 1,2 %A A190686 _Clark Kimberling_, May 17 2011