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Numbers k that divide the (left) concatenation of all numbers <= k written in base 13 (most significant digit on left).
1

%I #26 Jun 01 2024 04:41:00

%S 1,3,9,15,21,35,53,64,105,192,320,448,576,960,1344,2583,2611,2688,

%T 4480,5760,8064,8865,12160,13440,23168,28413,131727,201349,654231,

%U 901299,1121799,2629184,11874240,13712832,35644608,68560525,76680065,79404800,97064075

%N Numbers k that divide the (left) concatenation of all numbers <= k written in base 13 (most significant digit on left).

%C a(84) > 3*10^10. - _Jason Yuen_, May 31 2024

%H Jason Yuen, <a href="/A029482/b029482.txt">Table of n, a(n) for n = 1..83</a>

%H <a href="/index/N#concat">Index entries for related sequences</a>

%t b = 13; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[IntegerDigits[#, b], c], b], #] &] (* _Robert Price_, Mar 12 2020 *)

%Y Cf. A029447-A029470, A029471-A029494, A029495-A029518, A029519-A029542, A061931-A061954, A061955-A061978.

%K nonn,base

%O 1,2

%A _Olivier Gérard_

%E More terms from Andrew Gacek (andrew(AT)dgi.net), Feb 20 2000

%E More terms from Larry Reeves (larryr(AT)acm.org), May 24 2001

%E Edited and updated by Larry Reeves (larryr(AT)acm.org), Apr 12 2002

%E a(29)-a(39) from _Max Alekseyev_, May 16 2011