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Champernowne sequence: write n in base 8 and juxtapose.
16

%I #25 Sep 08 2022 08:45:01

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

%T 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,

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

%N Champernowne sequence: write n in base 8 and juxtapose.

%C Apart from the initial term, identical to A031035.

%C Should not be merged with A031035 because there are many sequences which depend on the latter starting with a 1. - _N. J. A. Sloane_, Jan 30 2010

%C An irregular table in which the n-th row lists the base-8 digits of n. - _Jason Kimberley_, Dec 07 2012

%C The base-8 Champernowne constant: it is normal in base 8. - _Jason Kimberley_, Dec 07 2012

%t Flatten[ IntegerDigits[ Range[0, 40], 8]] (* or *)

%t 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, 0] (* _Robert G. Wilson v_, Jun 29 2014 *)

%o (Magma) [0]cat &cat[Reverse(IntegerToSequence(n,8)):n in[1..31]]; // _Jason Kimberley_, Dec 07 2012

%o (Python)

%o from itertools import count, chain, islice

%o from sympy.ntheory.factor_ import digits

%o def A054634_gen(): return chain.from_iterable(digits(m, 8)[1:] for m in count(0))

%o A054634_list = list(islice(A054634_gen(), 30)) # _Chai Wah Wu_, Jan 07 2022

%Y Cf. A007376, A030190, A007094.

%Y 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), A031035 and this sequence (b=8), A031076 (b=9), A007376 and A033307 (b=10). - _Jason Kimberley_, Dec 06 2012

%K nonn,base,cons,easy,tabf

%O 0,3

%A _N. J. A. Sloane_, Apr 16 2000