Divisibility by p^p: A, B, C Sol'ns & More

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Discussion Overview

The discussion revolves around the properties of the expression Ap - Bp - Cp in relation to divisibility by pp, specifically for prime values of p greater than 2. Participants explore whether specific integer values A, B, and C can be found that satisfy certain divisibility conditions, and whether these findings relate to Fermat's Last Theorem.

Discussion Character

  • Exploratory
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant claims to have found integers A, B, and C such that Ap - Bp - Cp is of the form N*pp with N not divisible by p+2 or p, working for p = 3, 4, and 5.
  • Another participant questions the validity of the claim for p = 4, suggesting it may only hold for odd primes.
  • A later reply provides a specific numerical example for p = 4, indicating the sum is not divisible by 44.
  • Some participants propose that the conditions can be satisfied for all values of B and C as long as B + C = A and neither B nor C is divisible by p.
  • One participant expresses skepticism about the ease of proving the findings, suggesting that claims of simplicity often mask deeper complexities.
  • Another participant asserts that the findings do not constitute a proof of Fermat's Last Theorem, emphasizing the historical context and established proof by Andrew Wiles.
  • Concerns are raised about the implications of finding specific A, B, and C values, with one participant arguing that this does not generalize to all possible integers.

Areas of Agreement / Disagreement

Participants express differing views on the validity of the findings, particularly regarding their applicability to all primes and their relevance to Fermat's Last Theorem. There is no consensus on whether the proposed integers A, B, and C can be generalized or if they provide a valid proof of the theorem.

Contextual Notes

Some participants note that numerical examples for primes greater than 3 are difficult to verify due to large values involved. Additionally, there are unresolved questions regarding the assumptions made about the integers A, B, and C and their relationships.

Terry Coates
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I have found how to get three integers A B and C such that A^p - B^p - C^p is of form N*p^p with p > 2 and N not divisible by p+2.or p.
This is A = p^(p-1) , B = A-1, C = 1 . This works with p = 3 , 4 and 5.
My questions are: does it work with all values of p > 2 and is there any other way of achieving these properties?
 
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Sorry not with p = 4, but probably with all primes.
 
For ##p=4## I get ##1.024.254## for the sum which is not divisible by ##4^4=256\,##.
 
Terry Coates said:
I have found how to get three integers A B and C such that A^p - B^p - C^p is of form N*p^p with p > 2 and N not divisible by p+2.or p.
This is A = p^(p-1) , B = A-1, C = 1 . This works with p = 3 , 4 and 5.
My questions are: does it work with all values of p > 2 and is there any other way of achieving these properties?
You get it for all odd ##p## which can be proven by the expansion ##(a-1)^n=\sum_{k=0}^{n} \binom{n}{k}(-1)^{n-k}a^k\,##. You simply subtracted the terms for ##k=0## and ##k=n## and the rest is divisible by ##a## and by ##n##.
 
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It also works for all values of B and C with B + C = A as long as B and C are not divisible by p. eg for p= 3 B,C = 8,1 or 7,2 or 5,4
Numerical examples for p higher than 3 are not possible to verify, due to the very large values involved. However from an algebraic expression it is easily shown how this is true for all prime values of p

You may have guessed my interest is in Fermat's last theorem, and the findings here seem to be the simple proof of this, since the condition of divisibility by p^p is necessary if A^p - B^p - C^p = 0 , and this divisibility is only possible in the way I show, where the sum is always greater than zero.
So have I hit on Fermat's proof? That is for all prime values of p which is considered all that is needed. (p = 4 having been proved di8fferently)
 
Terry Coates said:
It also works for all values of B and C with B + C = A as long as B and C are not divisible by p. eg for p= 3 B,C = 8,1 or 7,2 or 5,4
Numerical examples for p higher than 3 are not possible to verify, due to the very large values involved.
They are, but what for? You may find as many examples as you want, and still have no proof.
However from an algebraic expression it is easily shown how this is true for all prime values of p
When I read sentences like this, I usually immediately stop reading. In nine of ten cases, it is wrong what's hidden behind easily. If it was so easy, why don't tell us?
You may have guessed my interest is in Fermat's last theorem, ...
... which has been proven by Andrew Wiles and history as well as proof are strong indications, that there is no short way to it.
... and the findings here seem to be the simple proof of this, since the condition of divisibility by p^p is necessary if A^p - B^p - C^p = 0 , and this divisibility is only possible in the way I show, where the sum is always greater than zero.
Unproven statement and irrelevant to the case.
So have I hit on Fermat's proof?
No. I dare to claim this without any inspection. One of the few cases in math, where evidence is almost as good as a proof.
That is for all prime values of p which is considered all that is needed. (p = 4 having been proved di8fferently)
Sorry, but the chances to find a simple proof for FLT are literally zero.
 
You have shown that there are specific numbers A,B,C such that Ap-Bp-Cp is a non-zero value that has some known prime factor. That doesn't tell us anything about other A,B,C.
 

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