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A029533
Numbers k such that k divides the (left) concatenation of all numbers <= k written in base 16 (most significant digit on right).
1
1, 3, 5, 9, 15, 19, 21, 43, 57, 255, 345, 385, 505, 1131, 1395, 1585, 7205, 11565, 38949, 270425, 684555, 8311925
OFFSET
1,2
COMMENTS
This sequence differs from A061969 in that all least significant zeros are removed before concatenation.
No more terms < 10^7. [Lars Blomberg, Sep 20 2011]
EXAMPLE
See A029519 for example.
MATHEMATICA
b = 16; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[IntegerDigits[IntegerReverse[#, b], b], c], b], #] &] (* Robert Price, Mar 13 2020 *)
KEYWORD
nonn,base,more
EXTENSIONS
Edited and updated by Larry Reeves (larryr(AT)acm.org), Apr 12 2002
Additional comments and more terms from Larry Reeves (larryr(AT)acm.org), Jun 04 2001
a(21)-a(22) from Lars Blomberg, Sep 20 2011
STATUS
approved