A061947 Numbers n such that n divides the (right) concatenation of all numbers <= n written in base 18 (most significant digit on right).

1, 2, 3, 6, 9, 17, 47, 61, 69, 137, 323, 385, 674, 731, 884, 1245, 1253, 17204, 35580, 37282, 73270, 74919, 78625, 98413, 119017, 263197, 313732, 402321, 467738, 661300, 4757138, 8445220, 9481937

Offset: 1

Author

Larry Reeves (larryr(AT)acm.org), May 24 2001

Keywords

• nonn
• base
• more

Comments

This sequence differs from A029511 in that all least significant zeros are removed before concatenation.

No more terms < 10^7. - Lars Blomberg, Oct 23 2011

Examples

			See A061931 for example.
		

Links

• Index entries for related sequences

Crossrefs

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

Programs

Mathematica

b = 18; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[c, IntegerDigits[IntegerReverse[#, b], b]], b], #] &] (* Robert Price, Mar 08 2020 *)

PARI

lista(nn) = my(s, t); for(k=1, nn, s=k/18^valuation(k, 18); while(s, t=t*18+s%18; s\=18); if(t%k==0, print1(k, ", "))); \\ Jinyuan Wang, Dec 05 2020

Extensions

Edited and updated by Larry Reeves (larryr(AT)acm.org), Apr 12 2002

a(29)-a(33) from Lars Blomberg, Oct 23 2011