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 A209886 #6 Mar 30 2012 17:30:05 %S A209886 2,7,13,18,24,29,31,36,42,47,53,58,64,69,71,76,82,87,93,98,104,110, %T A209886 115,121,126,132,137,143,149,154,160,165,171,176,178,183,189,194,200, %U A209886 205,211,217,222,228,233,239,244,246,251,257,262,268,273,279,285,290 %N A209886 Numbers such that A172470(n) = 52. %Y A209886 Cf. A172470. %K A209886 nonn %O A209886 1,1 %A A209886 _Stephen Crowley_, Mar 14 2012