A031035 Write n in base 8 and juxtapose.

1, 2, 3, 4, 5, 6, 7, 1, 0, 1, 1, 1, 2, 1, 3, 1, 4, 1, 5, 1, 6, 1, 7, 2, 0, 2, 1, 2, 2, 2, 3, 2, 4, 2, 5, 2, 6, 2, 7, 3, 0, 3, 1, 3, 2, 3, 3, 3, 4, 3, 5, 3, 6, 3, 7, 4, 0, 4, 1, 4, 2, 4, 3, 4, 4, 4, 5, 4, 6, 4, 7, 5, 0, 5, 1, 5, 2, 5, 3, 5, 4, 5, 5, 5, 6, 5, 7, 6, 0, 6

Offset: 1

Author

Clark Kimberling

Keywords

• nonn
• base
• cons
• easy
• tabf

Comments

Apart from the initial term, identical to A054634.

Should not be merged with A054634 because there are many sequences which depend on this sequence starting with a 1. - N. J. A. Sloane, Jan 30 2010

An irregular table in which the n-th row lists the base-8 digits of n. - Jason Kimberley, Dec 07 2012

The base-8 Champernowne constant: it is normal in base 8. - Jason Kimberley, Dec 07 2012

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Tables in which the n-th row lists the base b digits of n: A030190 and A030302 (b=2), A003137 and A054635 (b=3), A030373 (b=4), A031219 (b=5), A030548 (b=6), A030998 (b=7), this sequence and A054634 (b=8), A031076 (b=9), A007376 and A033307 (b=10). - Jason Kimberley, Dec 06 2012

Cf. A007094.

Programs

Magma

&cat[Reverse(IntegerToSequence(n,8)):n in[1..31]]; // Jason Kimberley, Dec 07 2012

Maple

seq(op(ListTools:-Reverse(convert(n,base,8))),n=1..100); # Robert Israel, Nov 12 2024

Mathematica

Flatten[ IntegerDigits[ Range[40], 8]] (* or *)
almostNatural[n_, b_] := Block[{m = 0, d = n, i = 1, l, p}, While[m <= d, l = m; m = (b - 1) i*b^(i - 1) + l; i++]; i--; p = Mod[d - l, i]; q = Floor[(d - l)/i] + b^(i - 1); If[p != 0, IntegerDigits[q, b][[p]], Mod[q - 1, b]]]; Array[ almostNatural[#, 8] &, 105] (* Robert G. Wilson v, Jun 29 2014 *)

Python

from itertools import count, islice
from sympy.ntheory.factor_ import digits
def A031035_gen(): return (d for m in count(1) for d in digits(m,8)[1:])
A031035_list = list(islice(A031035_gen(),30)) # Chai Wah Wu, Jan 07 2022