A029538 Numbers n such that n divides the (left) concatenation of all numbers <= n written in base 21 (most significant digit on right).

1, 5, 40, 65, 80, 928, 1504, 4568, 4640, 4880, 5065, 11201, 31145, 40555, 89480, 812645, 1281320

Offset

1,2

Comments

This sequence differs from A061974 in that all least significant zeros are removed before concatenation.

No more terms < 10^7. [Lars Blomberg, Sep 26 2011]

Links

Table of n, a(n) for n=1..17.

Index entries for related sequences

Example

See A029519 for example.

Mathematica

b = 21; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[IntegerDigits[IntegerReverse[#, b], b], c], b], #] &] (* Robert Price, Mar 13 2020 *)

Crossrefs

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

Sequence in context: A299815 A371557 A222366 * A153795 A015874 A244725

Adjacent sequences: A029535 A029536 A029537 * A029539 A029540 A029541

Keyword

nonn,base,more

Author

Olivier Gérard

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), May 25 2001

a(16)-a(17) from Lars Blomberg, Sep 26 2011

Status

approved