%I #22 Jul 26 2021 01:46:13
%S 1,3,9,12,36,96,128,2267,4031,29416,551444,2033727,2056797,2477144,
%T 7974180,9482385
%N Numbers k such that k divides the (left) concatenation of all numbers <= k written in base 7 (most significant digit on right).
%C This sequence differs from A061960 in that all least significant zeros are removed before concatenation.
%C No more terms < 10^7. [_Lars Blomberg_, Sep 07 2011]
%H <a href="/index/N#concat">Index entries for related sequences</a>
%e See A029519 for example.
%t b = 7; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[IntegerDigits[IntegerReverse[#, b], b], c], b], #] &] (* _Robert Price_, Mar 13 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 Edited and updated by Larry Reeves (larryr(AT)acm.org), Apr 12 2002; Aug 25, 2002
%E a(12)-a(16) from _Lars Blomberg_, Sep 07 2011
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