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Numbers k that divide the (right) concatenation of all numbers <= k written in base 7 (most significant digit on left).
1

%I #13 Jul 03 2021 23:23:46

%S 1,3,7,12,21,28,44,49,60,61,63,81,84,91,97,108,140,147,180,189,196,

%T 204,212,243,252,303,308,324,343,349,376,392,441,504,831,1029,1057,

%U 1176,1561,2401,2744,3101,4312,5096,6027,7203,8232,10339,11669,12936,13755

%N Numbers k that divide the (right) concatenation of all numbers <= k written in base 7 (most significant digit on left).

%H Robert Price, <a href="/A029452/b029452.txt">Table of n, a(n) for n = 1..76</a>

%t b = 7; c = {}; Select[Range[10^5], Divisible[FromDigits[c = Join[c, IntegerDigits[#, b]], b], #] &] (* _Robert Price_, Mar 11 2020 *)

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

%K nonn,base

%O 1,2

%A _Olivier GĂ©rard_

%E More terms from _David W. Wilson_