A029520 Numbers k such that k divides the (left) concatenation of all numbers <= k written in base 3 (most significant digit on right and removing all least significant zeros before concatenation).

1, 4, 5, 7, 19, 443, 19952, 81544, 919648, 1186844

Offset: 1

Author

Olivier Gérard

Keywords

• nonn
• base
• more

Comments

This sequence differs from A061956 in that all least significant zeros are removed before concatenation.

No more terms < 10^7. [Lars Blomberg, Sep 02 2011]

Examples

			See A029519 for example.
		

Links

• Index entries for related sequences

Crossrefs

Cf. A029447-A029470, A029471-A029494, A029495-A029518, A029519-A029542, A061931-A061954, A061955-A061978.

Programs

J

ab=. #.^:_1
mkcat=. [ ab&.> [ #.&.> [ |.@:ab&.> [: |. [: >: [: i. ]
seq=. ] +. [ #. [: ; mkcat
3 (] #~ ] = seq"0) >: i.500x NB. Stephen Makdisi, May 03 2018

Mathematica

b = 3; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[IntegerDigits[IntegerReverse[#, b], b], c], b], #] &] (* Robert Price, Mar 13 2020 *)

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(9)-a(10) from Lars Blomberg, Sep 02 2011