How or where could I find the proof of Denjoy's probability argument for the Mertens function
$ M(x) = \sum_{n=1}^x \mu(n) = O(x^{1/2}+e) $ with $e \to 0$ based on the fact that the Möbius function $ \mu(n)$ behaves as a random variable that takes the values $\{-1,1\}$ with same probability $\frac12$?
Is there a similar probabilistic interpretation for problems inside number theory?