$a^a+b^b=c^c$ (are there any solutions over positive integers?)

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Does $a^a+b^b=c^c$ have solutions over positive integers?

I did not try almost anything because I do not know how to handle these kind of questions.

I did not find this question anywhere, just created it so that I have something to calculate and think about, but, unfortunately, I do not know enough of number theory to attack this problem.

Do you have any ideas?

It could be that this is not at all hard, but at this moment I do not have a clever idea.

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There are no solutions over the positive integers.

Without loss of generality, $a \le b$. Then the left hand side is bounded by $2b^b$; on the other hand, $c > b$ and the right hand side is therefore at least

$$c^c \ge (b + 1)^{b + 1} > b^b \cdot (b + 1) \ge 2 b^b$$

giving a contradiction.