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.

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A195109 Inverse permutation of A195108; every positive integer occurs exactly once.

Original entry on oeis.org

1, 2, 3, 6, 4, 5, 9, 7, 10, 8, 13, 15, 11, 14, 12, 21, 18, 20, 16, 19, 17, 27, 24, 26, 28, 22, 25, 23, 34, 31, 36, 33, 35, 29, 32, 30, 42, 45, 39, 44, 41, 43, 37, 40, 38, 55, 51, 54, 48, 53, 50, 52, 46, 49, 47, 65, 61, 64, 58, 66, 63, 60, 62, 56, 59, 57, 76, 72, 75
Offset: 1

Views

Author

Clark Kimberling, Sep 09 2011

Keywords

Crossrefs

Programs

A195107 Fractalization of the fractal sequence A004736. Interspersion fractally induced by A004736.

Original entry on oeis.org

1, 1, 2, 3, 1, 2, 3, 1, 4, 2, 3, 5, 1, 4, 2, 6, 3, 5, 1, 4, 2, 6, 3, 5, 7, 1, 4, 2, 6, 3, 8, 5, 7, 1, 4, 2, 6, 9, 3, 8, 5, 7, 1, 4, 2, 10, 6, 9, 3, 8, 5, 7, 1, 4, 2, 10, 6, 9, 3, 11, 8, 5, 7, 1, 4, 2, 10, 6, 9, 12, 3, 11, 8, 5, 7, 1, 4, 2, 10, 6, 13, 9, 12, 3, 11, 8, 5, 7, 1, 4, 2, 10, 14
Offset: 1

Views

Author

Clark Kimberling, Sep 09 2011

Keywords

Comments

See A194959 for a discussion of fractalization and the interspersion fractally induced by a sequence. The sequence A004736 is the fractal sequence obtained by concatenating the segments 1; 2,1; 3,2,1; 4,3,2,1;...

Crossrefs

Programs

  • Mathematica
    j[n_] := Table[n + 1 - k, {k, 1, n}]; t[1] = j[1];
    t[n_] := Join[t[n - 1], j[n]]   (* A004736 *)
    t[10]
    p[n_] := t[20][[n]]
    g[1] = {1}; g[n_] := Insert[g[n - 1], n, p[n]]
    f[1] = g[1]; f[n_] := Join[f[n - 1], g[n]]
    f[20] (* A195107 *)
    row[n_] := Position[f[30], n];
    u = TableForm[Table[row[n], {n, 1, 5}]]
    v[n_, k_] := Part[row[n], k];
    w = Flatten[Table[v[k, n - k + 1], {n, 1, 13},
    {k, 1, n}]] (* A195108 *)
    q[n_] := Position[w, n]; Flatten[Table[q[n],
    {n, 1, 80}]] (* A195109 *)
Showing 1-2 of 2 results.