A029477 Numbers k that divide the (left) concatenation of all numbers <= k written in base 8 (most significant digit on left).

1, 7, 13, 17, 35, 49, 65, 245, 305, 679, 889, 1421, 2231, 2891, 3623, 31943, 59365, 113141, 143755, 193595, 367673, 414545, 1133461, 4916897, 201152387, 1347933505, 1409041697, 1462237105

Offset: 1

Author

Olivier Gérard

Keywords

• nonn
• base
• more

Comments

No other terms below 3*10^10.

Examples

			For k=7, we have 7654321_8 which is 2054353_10, and 2054353 = 7*293479.
		

Links

• Index entries for related sequences

Crossrefs

Cf. A007094.

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

Programs

Mathematica

b = 8; c = {}; Select[Range[10^4], Divisible[FromDigits[c = Join[IntegerDigits[#, b], c], b], #] &] (* Robert Price, Mar 12 2020 *)

PARI

isok(k) = my(list=List()); forstep(i=k, 1, -1, my(d=digits(i, 8)); for (j=1, #d, listput(list, d[j]));); (fromdigits(Vec(list), 8) % k) == 0; \\ Michel Marcus, May 20 2024

Extensions

More terms from Andrew Gacek (andrew(AT)dgi.net), Feb 20 2000

More terms from Larry Reeves (larryr(AT)acm.org), Jun 01 2001

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

a(23)-a(24) from Max Alekseyev, May 14 2011

a(25)-a(28) from Jason Yuen, May 19 2024