Is the Expanded Collatz Sequence Unique for Each k Value?

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Discussion Overview

The discussion centers on the exploration of an expanded version of the Collatz sequence, specifically the modification of the sequence by replacing the traditional 3n+1 rule with 3n+2k+1 for varying integer values of k. Participants are investigating whether the cycles produced by this expanded sequence are unique for each k value and how these cycles differ from the original sequence.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants question whether the expanded Collatz sequence has been previously explored, noting the existence of various generalizations listed on Wikipedia.
  • One participant references the Syracuse function as a potential comparison to their proposed expansion of the Collatz sequence.
  • Another participant suggests that their expanded form may already be covered as a special case of a generalization explored by Conway.
  • A participant outlines the mechanics of the expanded sequence, indicating that for k=0, the original sequence is obtained, while for k>0, different cycles emerge, such as the cycle 3-12-6-3 for k=1.
  • There is a focus on investigating what cycles the sequence iterates to for different values of k and whether these cycles are unique for each k, independent of the initial seed number.

Areas of Agreement / Disagreement

Participants do not appear to reach a consensus on whether the expanded Collatz sequence has been previously studied or if it represents a unique exploration. Multiple competing views regarding the uniqueness of cycles for different k values remain unresolved.

Contextual Notes

The discussion does not clarify the assumptions underlying the proposed modifications to the Collatz sequence or the implications of the cycles for different k values. There is also no resolution on the mathematical properties of the expanded sequence.

elcaro
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TL;DR
Expanding the Collatz sequence by replacing 3n+1 with 3n+2k+1 for k=0,1,2,...
For k=0 we get the original sequence, leading to the cycle 4-2-1. If the Collatz conjecture holds, that would be true for all integer values of n>0.
For values of k>0 we get different cycles.
For k=1 we for instance get the cycle 3-12-6-3
What we want to investigate is:
- What cycle is the sequence iterating to for different values of k?
- Is that cycle unique for k (independent of the seed number)?
Has this expanded Collatz sequence been explored previously?
 
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elcaro said:
TL;DR Summary: Expanding the Collatz sequence by replacing 3n+1 with 3n+2k+1 for k=0,1,2,...
For k=0 we get the original sequence, leading to the cycle 4-2-1. If the Collatz conjecture holds, that would be true for all integer values of n>0.
For values of k>0 we get different cycles.
For k=1 we for instance get the cycle 3-12-6-3
What we want to investigate is:
- What cycle is the sequence iterating to for different values of k?
- Is that cycle unique for k (independent of the seed number)?

Has this expanded Collatz sequence been explored previously?
If you want to have more information about the cycle(s) of Collatz, watch this short video on Youtube:
 

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