Hurkyl said:
Your abstract alone makes me quite skeptical -- you don't even claim to have a proof, you merely claim that your goal was a proof.
The introduction makes me even more skeptical -- it doesn't even mention the possibility that you are providing a proof, and the main thing it seems to attempt is only mentioned as a "possibility".
Sure, though it isn't necessarily of any use; for instance, a = 1, b = 1, and c = x satisfies this assumption, although it is entirely uninteresting.
But I see no reason why we could make this assumption.
Anyways, continuing on for the sake of argument...
What if s is zero but t is not?
Thus far, you've given no reason to think that bc cannot divide f(z, k).
This directly contradicts your previous assumption that sets x = abc. (unless c = 1)
Why would we know that?
"Why would we know that?"
If we can agree on the validity of the derivation of the equation
(z-y) = k = (x")^n, then, based on symmetry, (z-x) = l = (y")^n and
(x+y) = m = (z")^n
If we can't agree that (z-y) = k = (x")^n then let's consider the case where n = 3.
3zyk = x^3 - k^3 Since x^3 and k must have common factors let's assume x has three factors such that x^3 = (abc)^3
We can assume that x has only two factors or multiple factors, but for illustrative purposes let's just assume three.
Let's further assume that a does not have a common factor with k but b and c do have common factors with k. Let's assume further that k = bc.
Then, factoring out k, 3zy = (a^3)(bc)^2 - (bc)^2
Since x, y and z can have no common factors, bc, which is a factor of x, cannot be a factor of z or y; therefore the assumption that k = bc is invalid. If we assume k = (bc)^2 or bc^2 or cb^2, we can see that these assumptions are all invalid. The only assumption that does not violate the initial condition that x, y and z have no common factors is if k = (bc)^n
Since x>k, x must have at least two factors, one of which is the product of all the factors of x that are not common factors of k (let's call this x') and the other is the product of all the factors of x that are common factors of k (let's call this x"). In the example (x")^n = (bc)^n = k.
"What if s is zero and t is not?"
Let's use the n=3 example, then k = (b^3)c or (b^3)(c^2). In the latter case 3zy(b^3)(c^2) = (abc)^3 - [(b^3)(c^2)]^3
If we factor out k
3zy = (a^3)c - [(b^3)(c^2)]^2
Here again, c is a factor of the right hand side of the equation and a factor of x, so it should be a factor of the left side, but this is not possible without violating the initial condition prohibiting common factors.