Proof of Conjecture: n Not Prime => 2^n-1 Not Prime

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Homework Help Overview

The discussion revolves around a conjecture related to prime numbers, specifically stating that for an integer n greater than 1 that is not prime, the expression 2^n - 1 is also not prime. Participants are seeking clarification on the proof and its components.

Discussion Character

  • Exploratory, Conceptual clarification

Approaches and Questions Raised

  • Participants are questioning the derivation of the expression xy = 2^(ab) - 1 and expressing confusion regarding the notation 2^((a-1)b), wondering if it indicates some form of finiteness or indexing.

Discussion Status

The discussion appears to be ongoing, with participants actively seeking clarification on specific elements of the proof. There is mention of a missing proof attachment, which may be impacting the flow of the conversation.

Contextual Notes

One participant notes the absence of the proof attachment, which could be a barrier to understanding the conjecture fully. Additionally, there is a suggestion to start a new thread using a specific homework template, indicating a structured approach to the inquiry.

chimath35
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Conjecture: suppose n is an integer larger than 1 and n is not prime. Then 2^n-1 is not prime.

Proof attached.

Could someone please explain to me how they got to xy= 2^(ab)-1. I see the -1 part. Also I think I

do not understand the concept of 2^((a-1)b) I mean is it some index or some way of showing it is

finite? I am confused.
 
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The picture of the proof is showing up right?
 
I do not see any picture of the proof attached viewing this on the mobile app on my iPad or when I go to web view.
 
chimath35 said:
Conjecture: suppose n is an integer larger than 1 and n is not prime. Then 2^n-1 is not prime.

Proof attached.

Could someone please explain to me how they got to xy= 2^(ab)-1. I see the -1 part. Also I think I

do not understand the concept of 2^((a-1)b) I mean is it some index or some way of showing it is

finite? I am confused.

There is no attachment.

Please start a new thread using the homework template, and showing what you have done. I am closing this thread.
 

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