A029503 Numbers n such that n divides the (right) concatenation of all numbers <= n written in base 10 (most significant digit on right).

1, 2, 3, 5, 6, 9, 101, 107, 153, 167, 277, 414, 486, 858, 1659, 2894, 3093, 4299, 4842, 8838, 22734, 31869, 69492, 361057, 429786, 462018, 859002, 1170801, 1334667, 1663923, 6143512, 6162396, 6212646, 7034661, 8164443

Offset

1,2

Comments

This sequence differs from A061939 in that all least significant zeros are kept during concatenation.

Right concatenation, reverse order.

No more terms < 10^7. - Lars Blomberg, Oct 06 2011

Links

Table of n, a(n) for n=1..35.

Index entries for related sequences

Example

n = 22 is not a term since 12345678901112131415161718191021222 is not divisible by 22.
See A029495 for other examples.

Mathematica

b = 10; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[c, Reverse[IntegerDigits[#, b]]], b], #] &] (* Robert Price, Mar 12 2020 *)

Prog

(PARI) isok(n) = my(s = ""); for (k=1, n, sk = digits(k); forstep (j=#sk, 1, -1, s = concat(s, sk[j]))); (eval(s) % n) == 0; \\ Michel Marcus, Jan 28 2017

Crossrefs

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

Sequence in context: A294634 A051896 A061939 * A133139 A162309 A014593

Adjacent sequences: A029500 A029501 A029502 * A029504 A029505 A029506

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(25)-a(35) from Lars Blomberg, Oct 06 2011

Status

approved