cp's OEIS Frontend

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.

A384002 Let S(n,j,k), j = 1..n, k = 1..A024718(n), where row 1 = {(0),(1)}, and row n = union of n-tuples whose sum m < n, and the n-tuples formed by appending m to the (n-1)-tuples in row n-1. Then T(n,j) = j-th tuple in row n of S read as a base n+1 number expressed in decimal.

Original entry on oeis.org

0, 1, 0, 1, 2, 3, 4, 0, 1, 2, 3, 4, 5, 6, 8, 9, 16, 17, 18, 20, 21, 32, 0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 12, 15, 16, 25, 26, 27, 28, 30, 31, 32, 35, 36, 50, 51, 52, 55, 56, 75, 125, 126, 127, 128, 130, 131, 132, 135, 136, 150, 151, 152, 155, 156, 175, 250, 251, 252, 255, 275, 375
Offset: 1

Views

Author

Michael De Vlieger, May 21 2025

Keywords

Examples

			Table begins:
  1:  0, 1;
  2:  0, 1, 2, 3, 4;
  3:  0, 1, 2, 3, 4, 5, 6, 8, 9, 16, 17, 18, 20, 21, 32;
  4:  0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 12, 15, 16, 25, 26, 27, 28, 30, 31, 32,
      35, 36, 50, 51, 52, 55, 56, 75, 125, 126, 127, 128, 130, 131, 132, 135,
      136, 150, 151, 152, 155, 156, 175, 250, 251, 252, 255, 275, 375;
  etc.
Row 2 of S is {(0, 0), (0, 1), (0, 2), (1, 0), (1, 1)}. Reading the tuples in row 2 as a base 3 number, we have row 2 of this sequence.
		

Crossrefs

Programs

  • Mathematica
    nn = 8; w[0] = {{0}};
    Do[If[n == 1, Set[w[1], {{0}, {1}}],
      Set[w[n], Union@ Join[Select[Tuples[Range[0, n - 1], n], Total[#] < n &],
        Map[Append[#, n - Total[#]] &, w[n - 1] ] ] ] ], {n, nn}];
    Table[Map[FromDigits[#, n + 1] &, w[n]], {n, 0, nn}]

Formula

T(n,j) = base n+1 expansion of j-th tuple in row n of A384001.
Length of row n = A024718(n).