Can anyone please verify/review this proof about primes?

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    Primes Proof
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Homework Help Overview

The discussion revolves around the conjecture that there are infinitely many prime numbers of the form n^2-2. Participants are reviewing a proof that lists several specific primes derived from this form.

Discussion Character

  • Exploratory, Conceptual clarification

Approaches and Questions Raised

  • The original poster presents a proof listing specific primes generated by the formula n^2-2 and seeks verification of its correctness. Some participants confirm the presence of additional primes, while others express confusion regarding the verification process.

Discussion Status

Participants are actively engaging with the proof, with some confirming the correctness of the primes listed. There is a sense of exploration regarding the verification of the proof, but no explicit consensus has been reached about its overall validity.

Contextual Notes

The original poster mentions a lack of answers in their textbook, which contributes to their desire for confirmation from others. The discussion reflects a focus on understanding the proof rather than simply confirming its correctness.

Math100
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Homework Statement
It has been conjectured that there are infinitely many primes of the form n^2-2. Exhibit five such primes.
Relevant Equations
None.
Proof: Suppose that there are infinitely many primes of the form n^2-2.
Then we have n^2-2=2^2-2=2,
n^2-2=3^2-2=7,
n^2-2=5^2-2=23,
n^2-2=7^2-2=47,
n^2-2=9^2-2=79.
Note that 2, 7, 23, 47, 79 are prime numbers.
Therefore, five such primes are 2, 7, 23, 47, 79.

Above is my proof/answer for this problem. Can anyone please review/verify it and tell me if it's correct?
 
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Correct. 167 is another one.
 
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fresh_42 said:
Correct. 167 is another one.
Yes, since 13^2-2=169-2=167.
 
Thank you so much for confirming.
 
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Six down, infinity to go...:hammer:
 
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Math100 said:
Homework Statement:: It has been conjectured that there are infinitely many primes of the form n^2-2. Exhibit five such primes.
Relevant Equations:: None.

Proof: Suppose that there are infinitely many primes of the form n^2-2.
Then we have n^2-2=2^2-2=2,
n^2-2=3^2-2=7,
n^2-2=5^2-2=23,
n^2-2=7^2-2=47,
n^2-2=9^2-2=79.
Note that 2, 7, 23, 47, 79 are prime numbers.
Therefore, five such primes are 2, 7, 23, 47, 79.

Above is my proof/answer for this problem. Can anyone please review/verify it and tell me if it's correct?
I am puzzled. What part of this did you have trouble verifying? Checking your own work is an important part of learning math.
 
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FactChecker said:
I am puzzled. What part of this did you have trouble verifying? Checking your own work is an important part of learning math.
I just want to make sure if my proof is perfect and correct, because my textbook doesn't provide answers. And I want to get confirmation from experts.
 
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