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 A190852 #4 Mar 30 2012 18:57:29 %S A190852 1,2,4,5,7,8,9,13,14,16,17,21,22,25,26,28,29,32,33,37,40,43,44,49,50, %T A190852 52,53,56,57,64,65,67,69,76,79,80,85,86,88,89,97,98,100,101,104,105, %U A190852 112,113,117,121,128,129,130,133,134,148,149,151,152,157,158,160,161,169,170,172,173,176,177,193,194,196,197,200,201,202,208,209 %N A190852 Integers in (-1+A190808)/3; contains A190808 as a proper subsequence. %C A190852 See A190803. %t A190852 (See A190808.) %Y A190852 Cf. A190803, A190808, A190851. %K A190852 nonn %O A190852 1,2 %A A190852 _Clark Kimberling_, May 25 2011