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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A353962 Square array read by descending antidiagonals: The n-th row gives the decimal expansion of the base-n Champernowne constant.

Original entry on oeis.org

8, 6, 5, 2, 9, 4, 2, 8, 2, 3, 4, 9, 6, 1, 2, 0, 5, 1, 0, 3, 1, 1, 8, 1, 7, 9, 9, 1, 2, 1, 1, 3, 8, 4, 6, 1, 5, 6, 1, 6, 6, 4, 3, 4, 1, 8, 7, 1, 1, 2, 3, 2, 0, 2, 1, 6, 5, 1, 1, 6, 5, 6, 6, 3, 0, 0, 8, 3, 1, 1, 8, 5, 4, 2, 4, 9, 9, 0, 0, 8, 1, 1, 5, 3, 8, 4, 5, 9, 9, 9, 0
Offset: 2

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Author

Davis Smith, May 12 2022

Keywords

Comments

The base-n Champernowne constant (C_n) is normal in base n. A(n,k) is the (k+1)-th decimal digit of the fractional part of C_n.

Examples

			The square array A(n,k) begins:
  n/k | 0  1  2  3  4  5  6  7  8  9 10 11 ...
  ----+---------------------------------------
   2  | 8  6  2  2  4  0  1  2  5  8  6  8 ...
   3  | 5  9  8  9  5  8  1  6  7  5  3  8 ...
   4  | 4  2  6  1  1  1  1  1  1  1  1  1 ...
   5  | 3  1  0  7  3  6  1  1  1  1  1  1 ...
   6  | 2  3  9  8  6  2  6  8  5  8  1  5 ...
   7  | 1  9  4  4  3  5  5  3  5  0  8  6 ...
   8  | 1  6  3  2  6  4  8  1  2  1  0  5 ...
   9  | 1  4  0  6  2  4  9  7  6  1  1  9 ...
  10  | 1  2  3  4  5  6  7  8  9  1  0  1 ...
  ...
		

Crossrefs

Rows: A066716 (n=2), A077771 (n=3), A033307 (n=10).
Cf. A063945.

Programs

  • Mathematica
    A[n_,k_]:=Mod[Floor[ChampernowneNumber[n]10^(k + 1)] ,10]; Flatten[Table[Reverse[Table[A[n-k,k],{k,0,n-2}]],{n,2,14}]] (* Stefano Spezia, May 13 2022 *)

Formula

A(n,k) = floor(C_n*10^(k+1)) mod 10 where C_n (the base-n Champernowne constant) = Sum_{i>=1} i/(n^(i + Sum_{k=1..i-1} floor(log_n(k+1)))).