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 A031161 #21 Nov 25 2021 09:31:32 %S A031161 1,3,7,9,33,99,111,141,151,171,303,393,535,717,727,777,787,979,1441, %T A031161 1771,3003,3223,3663,5335,7447,9009,9339,9999,10501,11011,11811,11911, %U A031161 12121,12321,12621,13531,13831,14041,14541,14841,17671,18181 %N A031161 Palindromic lucky numbers. %H A031161 Kevin P. Thompson, <a href="/A031161/b031161.txt">Table of n, a(n) for n = 1..9932</a> (terms below 10^10, terms 1..760 from Robert G. Wilson v and terms 761..5862 from Amiram Eldar) %Y A031161 Intersection of A000959 and A002113. %K A031161 nonn,base %O A031161 1,2 %A A031161 _Patrick De Geest_