A061933 - OEIS

A061933

Numbers n such that n divides the (right) concatenation of all numbers <= n written in base 4 (most significant digit on right).

1, 2, 3, 9, 15, 21, 162, 495, 614, 813, 174913, 240389, 704162

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OFFSET

1,2

COMMENTS

This sequence differs from A029497 in that all least significant zeros are removed before concatenation.

The next term is > 400000. - _Larry Reeves_, Jan 16 2002

Next term exceeds 10000000. - Sean A. Irvine, Sep 03 2009

LINKS

Table of n, a(n) for n=1..13.

Index entries for related sequences

EXAMPLE

See A061931 for example.

MATHEMATICA

b = 4; c = {}; Select[Range[10^4], Divisible[FromDigits[

c = Join[c, IntegerDigits[IntegerReverse[#, b], b]], b], #] &] (* Robert Price, Mar 07 2020 *)

PROG

(PARI) lista(nn, m=4) = 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

CROSSREFS

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

Sequence in context: A294126 A091361 A092352 * A251239 A124881 A054416

Adjacent sequences: A061930 A061931 A061932 * A061934 A061935 A061936

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(13) from Sean A. Irvine, Sep 03 2009

STATUS

approved