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 A029505 #18 Mar 12 2020 21:19:24
%S A029505 1,2,3,4,6,11,106,616,990,1232,1276,1534,3494,8140,43054,52634,97691,
%T A029505 99280,131846,136006,355877,617749,824703,2115058,3011987
%N A029505 Numbers n such that n divides the (right) concatenation of all numbers <= n written in base 12 (most significant digit on right).
%C A029505 This sequence differs from A061941 in that all least significant zeros are kept during concatenation.
%C A029505 No more terms < 10^7. - _Lars Blomberg_, Oct 07 2011
%H A029505 <a href="/index/N#concat">Index entries for related sequences</a>
%e A029505 See A029495 for example.
%t A029505 b = 12; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[c, Reverse[IntegerDigits[#, b]]], b], #] &] (* _Robert Price_, Mar 12 2020 *)
%Y A029505 Cf. A029447-A029470, A029471-A029494, A029495-A029518, A029519-A029542, A061931-A061954, A061955-A061978.
%K A029505 nonn,base,more
%O A029505 1,2
%A A029505 _Olivier Gérard_
%E A029505 Edited and updated by Larry Reeves (larryr(AT)acm.org), Apr 12 2002
%E A029505 Additional comments and more terms from Larry Reeves (larryr(AT)acm.org), Jun 05 2001
%E A029505 a(22)-a(25) from _Lars Blomberg_, Oct 07 2011