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 A043270 #4 Mar 30 2012 18:56:34 %S A043270 0,1,2,3,4,5,6,7,8,9,10,2,4,6,8,10,12,14,16,18,20,2,3,4,5,6,7,8,9,10, %T A043270 11,12,4,5,6,7,8,9,10,11,12,13,14,6,7,8,9,10,11,12,13,14,15,16,8,9,10, %U A043270 11,12,13,14,15,16,17,18,10,11,12,13,14,15,16 %N A043270 Sum of the digits of the n-th base 11 palindrome. %Y A043270 A029956 (base 11 palindromes) %K A043270 nonn,base %O A043270 1,3 %A A043270 _Clark Kimberling_