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.

A160136 Lodumo_9 of Fibonacci numbers.

Original entry on oeis.org

0, 1, 10, 2, 3, 5, 8, 4, 12, 7, 19, 17, 9, 26, 35, 16, 6, 13, 28, 14, 15, 11, 44, 37, 18, 46, 55, 20, 21, 23, 53, 22, 30, 25, 64, 62, 27, 71, 80, 34, 24, 31, 73, 32, 33, 29, 89, 82, 36, 91, 100, 38, 39, 41, 98, 40, 48, 43, 109, 107, 45, 116, 125, 52, 42, 49, 118, 50, 51, 47, 134
Offset: 0

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Author

Philippe Deléham, May 02 2009

Keywords

Comments

Permutation of nonnegative integers.
From Michael De Vlieger, Jan 21 2021: (Start)
The plot is governed by A001175(9) = 24 and is bifurcated into two trajectories that repeat a "constellation" of points we label "red" and "blue" so as to match the linked figures. We might group the terms in a(n) into two classes as to their residue r (mod 24). The red terms have n = r (mod 24) for r in {1, 2, 6, 10, 11, 13, 14, 18, 22, 23}, while the blue terms have r in {0, 3, 4, 5, 7, 8, 9, 12, 15, 16, 17, 19, 20, 21}.
There are 10 residues in the red constellation, and 14 residues in the blue constellation.
For red, we have the displacement a(n + 24) - a(n) = 45, thus the slope m_red = 15/8. For blue, we have the displacement a(n + 24) - a(n) = 18, thus the slope m_blue = 3/4.(End)

Crossrefs

Programs

  • Mathematica
    Block[{m = 9, s = Fibonacci[Range[120]]}, Nest[Append[#1, Block[{k = 1}, While[Nand[Mod[k, m] == Mod[s[[#2]], m], FreeQ[#1, k]], k++]; k]] & @@ {#, Length@ #} &, {0}, 120]] (* Michael De Vlieger, Jan 21 2021 *)

Formula

a(n) = lod_9(A000045(n)).
a(n) = 2*a(n-24) - a(n-48) for n >= 48. - Philippe Deléham, Mar 09 2023
a(n) = a(n-12) + a(n-24) - a(n-36) for n >= 36. - Ray Chandler, Sep 10 2023

Extensions

Replaced second 18 by 118 - R. J. Mathar, May 03 2009