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.

A333853 The values >= 2 of A135303 for the odd numbers A333855(n), for n >= 1.

Original entry on oeis.org

2, 3, 2, 2, 3, 2, 2, 3, 4, 4, 4, 4, 3, 3, 2, 2, 2, 3, 4, 3, 2, 2, 9, 6, 3, 2, 4, 5, 2, 3, 3, 2, 2, 6, 2, 4, 2, 3, 2, 4, 2, 8, 2, 3, 6, 4, 4, 3, 3, 2, 4, 10, 3, 2, 5, 8, 16, 3, 4, 4, 6, 5, 3, 3, 4, 3, 2, 2, 2, 2
Offset: 1

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Author

Wolfdieter Lang, Jun 29 2020

Keywords

Comments

In Schick's book these are the B values, the number of periodic sequences, for the odd numbers N with B values >= 2. These numbers N are given in A333855.
In the complete coach system Sigma(b) of Hilton and Pedersen, these are the number of coaches for the odd numbers b from A333855 with more than one coach.
These are also the number of periodic modified doubling sequences for the odd numbers b from A333855 given in comments and examples by Gary W. Adamson, see his Aug 25 2019 comment in A065941, where this is named "r-t table" (for roots trajectory).

Examples

			n = 23: A333855(23) = 127 with A135303((127-1)/2) = A135303(63) = 9 = a(23). There are 9 Schick cycles (see also A333850), also 9 coaches, and also 9 modified doubling sequences.
		

References

  • Peter Hilton and Jean Pedersen, A Mathematical Tapestry: Demonstrating the Beautiful Unity of Mathematics, Cambridge University Press, 2010, pp. 261-264.
  • Carl Schick, Trigonometrie und unterhaltsame Zahlentheorie, Bokos Druck, Zürich, 2003 (ISBN 3-9522917-0-6). Tables 3.1 to 3.10, for odd p = 3..113 (with gaps), pp. 158-166.

Crossrefs

Programs

  • Mathematica
    Map[EulerPhi[#2]/(2 If[#2 > 1 && GCD[#1, #2] == 1, Min[MultiplicativeOrder[#1, #2, {-1, 1}]], 0]) & @@ {2, #} &, 1 + 2 Select[Range[2, 15000], 2 <= EulerPhi[#2]/(2 If[#2 > 1 && GCD[#1, #2] == 1, Min[MultiplicativeOrder[#1, #2, {-1, 1}]], 0]) & @@ {2, 2 # + 1} &]] (* Michael De Vlieger, Oct 15 2020 *)

Formula

a(n) = A135303((A333855(n)-1)/2), for n >= 1.