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.

Showing 1-3 of 3 results.

A194072 Inverse permutation to A194071; every positive integer occurs exactly once.

Original entry on oeis.org

1, 3, 2, 5, 6, 10, 4, 8, 9, 14, 7, 12, 13, 19, 15, 21, 11, 17, 18, 25, 20, 27, 28, 36, 16, 23, 24, 32, 26, 34, 35, 44, 22, 30, 31, 40, 33, 42, 43, 53, 45, 55, 29, 38, 39, 49, 41, 51, 52, 63, 54, 65, 66, 78, 37, 47, 48, 59, 50, 61, 62, 74, 64, 76, 77, 90, 46, 57, 58
Offset: 1

Views

Author

Clark Kimberling, Aug 14 2011

Keywords

Crossrefs

Cf. A194071.

Programs

A194070 Natural fractal sequence of A194069.

Original entry on oeis.org

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

Views

Author

Clark Kimberling, Aug 14 2011

Keywords

Comments

See A194029 for definitions of natural fractal sequence and natural interspersion.

Crossrefs

Programs

  • Mathematica
    z = 70;
    c[k_] := 1 + Floor[(2/3) k^2];
    c = Table[c[k], {k, 1, z}]  (* A194069 *)
    f[n_] := If[MemberQ[c, n], 1, 1 + f[n - 1]]
    f = Table[f[n], {n, 1, 300}]   (* A194070 *)
    r[n_] := Flatten[Position[f, n]]
    t[n_, k_] := r[n][[k]]
    TableForm[Table[t[n, k], {n, 1, 7}, {k, 1, 7}]]
    p = Flatten[Table[t[k, n - k + 1], {n, 1, 14}, {k, 1, n}]] (* A194071 *)
    q[n_] := Position[p, n]; Flatten[Table[q[n], {n, 1, 90}]] (* A194072 *)

A194069 1+floor((2/3)*n^2).

Original entry on oeis.org

1, 3, 7, 11, 17, 25, 33, 43, 55, 67, 81, 97, 113, 131, 151, 171, 193, 217, 241, 267, 295, 323, 353, 385, 417, 451, 487, 523, 561, 601, 641, 683, 727, 771, 817, 865, 913, 963, 1015, 1067, 1121, 1177, 1233, 1291, 1351, 1411
Offset: 1

Views

Author

Clark Kimberling, Aug 14 2011

Keywords

Crossrefs

Cf. A194070 (natural fractal sequence),
A194071 (natural fractal interspersion).

Programs

  • Mathematica
    c[k_]:=1+Floor[(2/3)k^2]; c=Table[c[k],{k,1,90}]

Formula

a(n)=1+floor(2*n^2/3).
a(n) = 1 +A030511(n+1). - R. J. Mathar, Aug 25 2011
Showing 1-3 of 3 results.