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 A138166 #9 Dec 16 2013 12:39:36 %S A138166 1,12,20,21,22,23,24,25,26,27,28,29,32,42,52,62,72,82,92,103,113,123, %T A138166 130,131,132,133,134,135,136,137,138,139,143,153,163,173,183,193,203, %U A138166 213,223,230,231,232,233,234,235,236,237,238,239,243,253,263,273,283 %N A138166 Numbers containing their length in their decimal representation. %H A138166 R. Zumkeller, <a href="/A138166/b138166.txt">Table of n, a(n) for n = 1..10000</a> %o A138166 (Haskell) %o A138166 import Data.List (isInfixOf) %o A138166 a138166 n = a138166_list !! (n-1) %o A138166 a138166_list = filter (\x -> show (a055642 x) `isInfixOf` show x) [0..] %o A138166 -- _Reinhard Zumkeller_, Jul 04 2012 %Y A138166 Cf. A055642, A138167, A138168. %Y A138166 Cf. A038528 (subsequence). %Y A138166 Cf. A052018, A119246. %K A138166 nonn,base %O A138166 1,2 %A A138166 _Reinhard Zumkeller_, Mar 03 2008