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%I #23 Jul 26 2021 01:46:37
%S 1,3,9,27,99,471,60237,1028301,1085427,2851947
%N Numbers k such that k divides the (left) concatenation of all numbers <= k written in base 10 (most significant digit on right).
%C This sequence differs from A061963 in that all least significant zeros are removed before concatenation.
%C No more terms < 10^7. - _Lars Blomberg_, Sep 12 2011
%H <a href="/index/N#concat">Index entries for related sequences</a>
%e See A029519 for example.
%t b = 10; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[IntegerDigits[IntegerReverse[#, b], b], c], b], #] &] (* _Robert Price_, Mar 13 2020 *)
%o (PARI) lista(nn, m=10) = my(c, s, t); for(k=1, nn, t+=m^c*s=fromdigits(Vecrev(digits(k, m)), m); c+=logint(s, m)+1; if(t%k==0, print1(k, ", "))); \\ _Jinyuan Wang_, Dec 05 2020
%Y Cf. A029447-A029470, A029471-A029494, A029495-A029518, A029519-A029542, A061931-A061954, A061955-A061978.
%K nonn,base,more
%O 1,2
%A _Olivier Gérard_
%E Edited and updated by Larry Reeves (larryr(AT)acm.org), Apr 12 2002
%E Additional comments from Larry Reeves (larryr(AT)acm.org), May 25 2001. a(7) from Larry Reeves (larryr(AT)acm.org) Jan 14 2002
%E a(8)-a(10) from _Lars Blomberg_, Sep 11 2011
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