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 A045638 #25 Jul 07 2025 04:01:59 %S A045638 0,3,6,9,33,66,99,111,141,171,222,252,282,303,333,363,393,414,444,474, %T A045638 525,555,585,606,636,666,696,717,747,777,828,858,888,909,939,969,999, %U A045638 1221,1551,1881,2112,2442,2772,3003,3333,3663,3993,4224,4554,4884,5115 %N A045638 Palindromic and divisible by 3. %H A045638 Harvey P. Dale, <a href="/A045638/b045638.txt">Table of n, a(n) for n = 1..2001</a> %t A045638 Select[Range[0,5500,3],PalindromeQ] (* _Harvey P. Dale_, Apr 14 2023 *) %Y A045638 Intersection of A002113 and A008585. %Y A045638 Cf. A029951, A045639, A043040, A045641, A045642, A045643, A045644, A083852. %K A045638 nonn,base %O A045638 1,2 %A A045638 _Jeff Burch_ %E A045638 Edited to include a(1) = 0 by _Paolo Xausa_, Jul 07 2025