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 A071275 #5 Dec 05 2013 19:55:20 %S A071275 1,2,3,4,5,6,7,8,9,101,111,202,121,212,303,131,222,313,404,141,232, %T A071275 323,414,505,151,242,333,424,515,606,161,252,343,434,525,616,707,171, %U A071275 262,353,444,535,626,717,808,181,272,363,454,545,636,727,818,909,10101 %N A071275 Palindromes in A071274. %e A071275 a(12) = 2112, a(1235) = 53211235 %Y A071275 Cf. A071273, A071274. %K A071275 base,nonn %O A071275 1,2 %A A071275 _Amarnath Murthy_, Jun 07 2002 %E A071275 Corrected and extended by _Sascha Kurz_, Jan 02 2003