%I #49 Jun 19 2024 14:49:21
%S 0,1,2,1,0,1,1,1,2,2,0,2,1,2,2,1,0,0,1,0,1,1,0,2,1,1,0,1,1,1,1,1,2,1,
%T 2,0,1,2,1,1,2,2,2,0,0,2,0,1,2,0,2,2,1,0,2,1,1,2,1,2,2,2,0,2,2,1,2,2,
%U 2,1,0,0,0,1,0,0,1,1,0,0,2,1,0,1,0,1,0,1,1,1,0,1,2,1,0,2,0,1,0,2,1
%N Champernowne sequence: write n in base 3 and juxtapose.
%C Essentially the same as A003137. - _R. J. Mathar_, Aug 29 2009
%C An irregular table in which the n-th row lists the base-3 digits of n. - _Jason Kimberley_, Dec 07 2012
%C The base-3 Champernowne constant (A077771): it is normal in base 3. - _Jason Kimberley_, Dec 07 2012
%H Reinhard Zumkeller, <a href="/A054635/b054635.txt">Rows n = 0..1000 of triangle, flattened</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/TernaryChampernowneConstant.html">Ternary Champernowne Constant</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Ternary_numeral_system">Ternary numeral system</a>
%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[#, 3] &, 105, 0] (* _Robert G. Wilson v_, Jun 29 2014 *)
%t First[RealDigits[ChampernowneNumber[3], 3, 100, 0]] (* _Paolo Xausa_, Jun 19 2024 *)
%o (Magma) [0]cat &cat[Reverse(IntegerToSequence(n,3)):n in[1..31]]; // _Jason Kimberley_, Dec 07 2012
%o (Haskell)
%o a054635 n k = a054635_tabf !! n !! k
%o a054635_row n = a054635_tabf !! n
%o a054635_tabf = map reverse a030341_tabf
%o a054635_list = concat a054635_tabf
%o -- _Reinhard Zumkeller_, Feb 21 2013
%o (Python)
%o from sympy.ntheory.digits import digits
%o def agen(limit):
%o for n in range(limit):
%o yield from digits(n, 3)[1:]
%o print([an for an in agen(35)]) # _Michael S. Branicky_, Sep 01 2021
%Y Cf. A054637 (partial sums).
%Y Cf. A081604 (row lengths), A053735 (row sums), A030341 (rows reversed), A007089, A077771.
%Y Table in which the n-th row lists the base b digits of n: A030190 and A030302 (b=2), A003137 and this sequence (b=3), A030373 (b=4), A031219 (b=5), A030548 (b=6), A030998 (b=7), A031035 and A054634 (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