Is this theorem Correct.

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If it is, is it trivial?

                                          **Theorem**

There does not exist a pythagorean triple $a^2 + b^2 = c^2$ $\{a,b,c \in \Bbb N\}$ where $b \ge a$ and $a|b$

                                          **PROOF**

Suppose $\exists$ a constant k {$k | k \ge 1, k \in \Bbb N$} and $k \cdot a$ forms a pythagorean triple with a.

I.e $a^2 + (k \cdot a)^2 = c^2$

$a^2 + k^2 \cdot a^2 =c^2 $

$a^2(k^2 + 1) = c^2$

$c = \sqrt{a^2(k^2 + 1)}$

$c = a \sqrt{k^2 + 1} $

$ \exists $ $ k: \sqrt{k^2 + 1} \in \Bbb Q$

However $\forall$ $ a \in \Bbb N$, $ a \ge 1$ $ \sqrt{a^2 + 1} \notin \Bbb Q$*

Where $ \Bbb Q$ is the set of rational numbers.

*: The proof of this theorem is left as an exercise to the reader.