%I #22 Jul 26 2021 01:46:28
%S 1,13,16,224,320,355,800,7856,8720,11683,18829,36464,42544,159125
%N Numbers k such that k divides the (left) concatenation of all numbers <= k written in base 9 (most significant digit on right).
%C This sequence differs from A061962 in that all least significant zeros are removed before concatenation.
%C No more terms < 10^7. - _Lars Blomberg_, Sep 09 2011
%H <a href="/index/N#concat">Index entries for related sequences</a>
%e See A029519 for example.
%t b = 9; 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=9) = 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 GĂ©rard_
%E Edited and updated by Larry Reeves (larryr(AT)acm.org), Apr 12 2002
%E Additional comments and more terms from Larry Reeves (larryr(AT)acm.org), May 25 2001
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