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.

A347067 Rectangular array (T(n,k)), by antidiagonals: T(n,k) = position of k in the ordering of {h/r^m, r = 1/sqrt(2), h >= 1, 0 <= m <= n}.

Original entry on oeis.org

2, 4, 4, 7, 8, 6, 9, 13, 13, 10, 12, 17, 21, 21, 15, 14, 21, 28, 33, 32, 19, 16, 22, 34, 44, 49, 40, 25, 19, 26, 35, 54, 66, 61, 51, 41, 21, 30, 41, 55, 82, 82, 78, 83, 63, 24, 35, 48, 65, 83, 102, 105, 126, 128, 95, 26, 38, 56, 76, 98, 103, 130, 169, 193
Offset: 1

Views

Author

Clark Kimberling, Sep 02 2021

Keywords

Examples

			Corner:
   2,  4,   7,   9,  12,  14,  16,  19,  21, ...
   4,  8,  13,  17,  21,  22,  26,  30,  35, ...
   6, 13,  21,  28,  34,  35,  41,  48,  56, ...
  10, 21,  33,  44,  54,  55,  65,  76,  88, ...
  15, 32,  49,  66,  82,  83,  98, 115, 133, ...
  19, 40,  61,  82, 102, 103, 122, 143, 165, ...
  25, 51,  78, 105, 130, 131, 156, 183, 210, ...
  41, 83, 126, 169, 210, 211, 252, 283, 310, ...
  ...
		

Crossrefs

Programs

  • Mathematica
    z = 100; r = N[1/Sqrt[2]];
    s[m_] := Range[z] r^m; t[0] = s[0];
    t[n_] := Sort[Union[s[n], t[n - 1]]]
    row[n_] := Flatten[Table[Position[t[n], N[k]], {k, 1, z}]]
    TableForm[Table[row[n], {n, 1, 10}]] (* A347067, array *)
    w[n_, k_] := row[n][[k]];
    Table[w[n - k + 1, k], {n, 12}, {k, n, 1, -1}] // Flatten (* A347067, sequence *)