What Are the Key Steps in Prime Number Proofs?

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Discussion Overview

The discussion revolves around the topic of prime numbers, specifically focusing on a problem related to Goldbach's conjecture and the steps involved in proving statements about sums of primes. Participants explore definitions, assumptions, and logical deductions necessary for constructing proofs involving prime numbers.

Discussion Character

  • Homework-related
  • Exploratory
  • Debate/contested

Main Points Raised

  • One participant seeks guidance on how to define a prime number in the context of a proof, indicating a need for clarity on foundational concepts.
  • Another participant suggests that defining a prime can be as simple as stating "Let p be a prime," emphasizing that a formula is not necessary.
  • A humorous remark is made about the difficulty of proving the conjecture, referencing a monetary bounty for a proof of Goldbach's conjecture.
  • Some participants clarify that the task is not to prove Goldbach's conjecture directly but rather to work with an assumption related to it.
  • One participant discusses the properties of odd numbers greater than 5 and how they can relate to even numbers greater than 2, proposing a logical pathway using n-3.
  • Another participant shares an anecdote about a challenging assignment related to Fermat's Last Theorem, drawing a parallel to the current problem and emphasizing the need for understanding specific primes like 3.

Areas of Agreement / Disagreement

Participants express differing views on the nature of the problem and the approach to defining primes. While some agree on the need for a clear definition, others focus on the logical structure of the proof without consensus on the best method to proceed.

Contextual Notes

There are unresolved assumptions regarding the definitions of primes and the implications of the conjectures being discussed. The discussion also highlights the complexity of proving statements related to prime numbers without reaching a definitive conclusion.

eku_girl83
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We didn't talk about prime numbers in my class, but several of the homework problems mention them.
For instance:
Prove that if every even natural number greater than 2 is the sum of two primes, then every odd natural number greater than 5 is the sume of three primes.

Assume that n is an even natural number and n is greater than 2.
Then n=2k, where k is an integer, and 2k is greater than 2.

But how do I define a prime number in a proof?
Any hints/help would be appreciated!
 
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But how do I define a prime number in a proof?

"Let p be a prime". You needn't find a formula for it in order to define it...
 
eku_girl83 said:
Prove that if every even natural number greater than 2 is the sum of two primes, then every odd natural number greater than 5 is the sume of three primes.

LOL!
if u ever prove this in your class ... do let me know and i will be happy to share the million dollars with u :biggrin:

http://www.acfnewsource.org/science/math_bounties.html
 
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Well, she wasn't exactly asked to prove Goldbach's conjecture, but rather some kind of corollary to a Goldbach-type conjecture which you're suppose to /assume/ to be correct.
 
It's good that you might want to use the definition of even in proofs and know how to do it.

But let's look at the example here using sums of primes. You're asked to deduce something about writing n=p+q+r where p,q,r are primes and n is odd and greater than 5. So it's n which has a certain property that you need to prove, you need nothing about p,q,r in the proof. So what properties does n have? it's odd and greater than 5, and what do we have a hypothesis for? even numbers greater than 2, yeah? so how can we relate n to an even number greater than 2? how about n-3? is that even and greater than 2? check, so what can we conclude about n-3 by hyptothesis? and hence n, since 3 is a prime?
 
Muzza said:
Well, she wasn't exactly asked to prove Goldbach's conjecture, but rather some kind of corollary to a Goldbach-type conjecture which you're suppose to /assume/ to be correct.

i know ... but can't i just kid around ?
i am sure eku would be happy to see that article ...
i recall my days when i wasted hours trying to prove it before i found out that even the best in the business are in the hunt .. that did invoke a bit of laughter ... prolly that's why life is so good ... somethings just level u with the best ... it let's u know u are not left far behind ...

duh! now see u got me writing philosophy :rolleyes:

-- AI
 
i know ... but can't i just kid around ?

Well, yes, but it seemed to me like you had misread the question.
 
i gave my elementary proofs class the following assignment: prove fermat's last theorem as follows:
assume: 1) if FLT is false, then there exists a stable elliptic curve which is not modular.
2) all stable elliptic curves are modular.

deduce that FLT is true.

notice one does not need to know the meanings of any of the technical words in this paragraph to prove the result.

your problem is a little harder. you do not need to know what a prime is but you do need to know 3 is a prime.

e.g. prove that if every even number greater than or equal to 2 is a sum of two donks, then every odd number greater than or equal to 5, is a sum of two donks and an odd number.
 
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