Digital Line Topology: Show Odd Integers are Dense in \mathbb{Z}

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Homework Help Overview

The problem involves demonstrating that the set of odd integers is dense in the digital line topology on the integers, denoted as \mathbb{Z}. The discussion centers around understanding the properties of this topology and the implications for the distribution of odd integers.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to reason about the density of odd integers by considering their placement relative to other integers. Some participants question the definition and implications of the 'digital topology,' seeking clarification on the notation used.

Discussion Status

Participants are actively engaging with the definitions and concepts related to the digital line topology. There is a recognition of the need to define terms more clearly, and some have expressed progress in their understanding. However, no consensus has been reached regarding the implications of the topology on the density of odd integers.

Contextual Notes

Participants are navigating the definitions of the digital line topology and its basis, with some noting the specific structure of open sets based on whether integers are odd or even. There is an acknowledgment of the complexity involved in interpreting these definitions.

cragar
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Homework Statement


Show that the set of odd integers is dense in
the digital line topology on [itex]\mathbb{Z}[/itex]

The Attempt at a Solution


if m in Z is odd then it gets mapped to the set {m}=> open
.
So is the digital line topology just the integers.
If I was given any 2 integers I could find an odd one in between if there is an element in between.
If I was given to consecutive integers I wouldn't be able to find an odd one in between but there are no elements in between in this set. And I thinking about this question correctly.
 
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Can you spell out what the 'digital topology' is? {m} doesn't mean much to me.
 
I think I got it figured out. thanks for having me define my terms better.
 
FYI:

I Googled "digital line topology" and found the following:

From http://www.math.csusb.edu/faculty/gllosent/About_me_files/555-Chapter2.pdf:
Example 1.10.

For each [itex]n\in\mathbb{Z}\,,[/itex] de fine:

[itex]\displaystyle \textit{B}(n) =\left\{\matrix{\{ n\},\ & \text{if }\ n \text{ is odd.} \\ \ \\ \{ n-1,\,n,\,n+1\}, & \text{if }\ n \text{ is even.}}\right.[/itex]

Consider [itex]\displaystyle {\frak{B}}= \{B(n)|n\in\mathbb{Z}\}[/itex]: a (basis of the*) digital line topology.​

* added by me, SammyS.
 

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