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 A191180 #4 Mar 30 2012 18:57:30 %S A191180 1,3,9,11,27,33,35,43,57,81,99,105,107,129,131,139,171,185,243,297, %T A191180 315,321,323,387,393,395,417,419,427,513,515,523,555,569,683,697,729, %U A191180 891,945,963,969,971,1161,1179,1185,1187,1251,1257,1259,1281,1283,1291 %N A191180 Integers in (A191128)/3; contains A191128 as a proper subsequence. %C A191180 See A191128. %t A191180 (See A191128.) %Y A191180 Cf. A191128, A191113. %K A191180 nonn %O A191180 1,2 %A A191180 _Clark Kimberling_, May 27 2011