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 A158849 #3 Mar 30 2012 18:52:03 %S A158849 1,22,333,4444,55555,666666,7777777,88888888,999999999,0,11,222,3333, %T A158849 44444,555555,6666666,77777777,888888888,9999999999,0,111,2222,33333, %U A158849 444444,5555555,66666666,777777777,8888888888,99999999999,0,1111 %N A158849 a(10n+m) is the integer with n+m concatenations of the digit m in base 10, 0<=m<=9. %Y A158849 A000461, A048376. %K A158849 nonn,base %O A158849 1,2 %A A158849 _Paul Curtz_, Mar 28 2009 %E A158849 Edited by _R. J. Mathar_, Apr 04 2009