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 A222724 #7 Mar 05 2013 21:13:06 %S A222724 1,111,121,141,161,171,1001,1111,1221,1331,1441,1551,1661,1771,1881, %T A222724 1991,10001,10101,10201,10401,10701,10801,10901,11011,11111,11211, %U A222724 11511,11611,11711,11811,11911,12021,12121,12221,12321,12521,12621,12921,13031,13131,13231 %N A222724 Palindromic nonprime numbers starting with a digit 1. %C A222724 Subsequence of A032350 (palindromic nonprime numbers) and A002113 (palindromic numbers). Complement of A222723 (palindromic primes starting with a digit 1) with respect to A043036 (palindromic numbers starting with a digit 1). %H A222724 Jaroslav Krizek, <a href="/A222724/b222724.txt">Table of n, a(n) for n = 1..1000</a> %Y A222724 Cf. A032350, A002113, A222723, A043036. %K A222724 nonn,base %O A222724 1,2 %A A222724 _Jaroslav Krizek_, Mar 03 2013