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 A029504 #18 Mar 12 2020 22:22:27
%S A029504 1,5,15,24,40,69,72,75,120,167,216,280,360,536,1192,1240,1360,11280,
%T A029504 25195,33216,33984,101328,221640,400479,531000,537640,600104,631155,
%U A029504 743085,958785,2660431,2777800
%N A029504 Numbers n such that n divides the (right) concatenation of all numbers <= n written in base 11 (most significant digit on right).
%C A029504 This sequence differs from A061940 in that all least significant zeros are kept during concatenation.
%C A029504 No more terms < 10^7. - _Lars Blomberg_, Oct 06 2011
%H A029504 <a href="/index/N#concat">Index entries for related sequences</a>
%e A029504 See A029495 for example.
%t A029504 b = 11; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[c, Reverse[IntegerDigits[#, b]]], b], #] &] (* _Robert Price_, Mar 12 2020 *)
%Y A029504 Cf. A029447-A029470, A029471-A029494, A029495-A029518, A029519-A029542, A061931-A061954, A061955-A061978.
%K A029504 nonn,base,more
%O A029504 1,2
%A A029504 _Olivier Gérard_
%E A029504 Edited and updated by Larry Reeves (larryr(AT)acm.org), Apr 12 2002; Aug 25, 2002
%E A029504 a(27)-a(32) from _Lars Blomberg_, Oct 06 2011