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 A117700 #10 Feb 16 2025 08:33:00 %S A117700 2,3,111,131,232,313,414,10301,12121,13331,14141,20102,20302,23132, %T A117700 24342,31313,32323,33133,34143,34343,40304,41114,42124,43334,44144, %U A117700 1003001,1013101,1111111,1123211,1141411,1221221,1223221,1241421,1303031,1313131,1331331,1411141 %N A117700 Palindromic primes in base 5 (written in base 5). %H A117700 Eric Weisstein: <a href="https://mathworld.wolfram.com/PalindromicPrime.html">Palindromic Prime</a>. %t A117700 Select[FromDigits[IntegerDigits[#, 5]]&/@Prime[Range[3200]], IntegerDigits[#] == Reverse[IntegerDigits[#]]&] (* _James C. McMahon_, Sep 25 2024 *) %Y A117700 Cf. A029973. %K A117700 nonn,base %O A117700 1,1 %A A117700 _Martin Renner_, Apr 13 2006 %E A117700 a(26)-a(37) from _James C. McMahon_, Sep 25 2024