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  "body": "\n## Summary\n\nIn general, exponentiation fails to be [[commutative|099E72KTF8]]. However, the equation $x^y = y^x$ has an infinity of solutions, consisting of the line $x=y$ and a smooth curve intersecting the line at $(e,e)$, where $e$ is Euler's number. The only integer solution that is on the curve is $2^4=4^2$.\n",
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