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A029527
Numbers k such that k divides the (left) concatenation of all numbers <= k written in base 10 (most significant digit on right).
1
1, 3, 9, 27, 99, 471, 60237, 1028301, 1085427, 2851947
OFFSET
1,2
COMMENTS
This sequence differs from A061963 in that all least significant zeros are removed before concatenation.
No more terms < 10^7. - Lars Blomberg, Sep 12 2011
EXAMPLE
See A029519 for example.
MATHEMATICA
b = 10; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[IntegerDigits[IntegerReverse[#, b], b], c], b], #] &] (* Robert Price, Mar 13 2020 *)
PROG
(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
KEYWORD
nonn,base,more
EXTENSIONS
Edited and updated by Larry Reeves (larryr(AT)acm.org), Apr 12 2002
Additional comments from Larry Reeves (larryr(AT)acm.org), May 25 2001. a(7) from Larry Reeves (larryr(AT)acm.org) Jan 14 2002
a(8)-a(10) from Lars Blomberg, Sep 11 2011
STATUS
approved