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A061939
Numbers n such that n divides the (right) concatenation of all numbers <= n written in base 10 (most significant digit on right).
2
1, 2, 3, 5, 6, 9, 99, 153, 189, 238, 252, 323, 444, 539, 927, 3099, 3753, 4224, 5451, 8967, 44544, 53673, 97119, 1423719, 3860793, 4773591
OFFSET
1,2
COMMENTS
This sequence differs from A029503 in that all least significant zeros are removed before concatenation.
No more terms < 10^7. - Lars Blomberg, Oct 20 2011
EXAMPLE
See A061931 for example.
MATHEMATICA
b = 10; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[c, IntegerDigits[IntegerReverse[#, b], b]], b], #] &] (* Robert Price, Mar 08 2020 *)
PROG
(PARI) lista(nn, m=10) = my(s, t); for(k=1, nn, s=k/m^valuation(k, m); while(s, t=t*m+s%m; s\=m); if(t%k==0, print1(k, ", "))); \\ Jinyuan Wang, Dec 05 2020
KEYWORD
nonn,base,more
AUTHOR
Larry Reeves (larryr(AT)acm.org), May 24 2001
EXTENSIONS
Edited and updated by Larry Reeves (larryr(AT)acm.org), Apr 12 2002
a(24)-a(26) from Lars Blomberg, Oct 20 2011
STATUS
approved