Distinct prime factorization function formulation to find mobius function?

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Background

I recently noticed the following:

$$ S(x)=\sum_{r=1}^\infty x^{p_r} $$

where $p_r$ is the $r$'th prime:

$$ \sum_{r=1}^\infty S(x^r) = \sum_{r=1}^\infty \frac{x^{p_r}}{(1-x^{p_r})} $$

However, we also notice that:

$$ \sum_{r=1}^\infty S(x^r) = \sum_{r=1}^\infty \frac{x^{p_r}}{(1-x^{p_r})} = \sum_{r=1}^\infty \omega(r) x^r $$

Where $\omega(r)$ is the number of distinct prime factors of $r$ and assigning $\omega(1)=0$ : http://mathworld.wolfram.com/DistinctPrimeFactors.html (More about it here)

Using the mobious inversion formula:

$$ S(x)=\sum_{r=1}^\infty x^{p_r} = \sum_{r=1}^\infty \sum_{s=1}^\infty \mu(s) \omega(r) x^{rs}$$

We know

$$ \sum_{r=1}^\infty x^{p_r} \sim \frac{1}{(x-1)\ln(1-x)}$$

as $x \nearrow 1$

Questions

Is this correct?

Does this already exist? (If, so I will be more than happy for a reference)?

I was wondering if using this above information (including the link) can one say anything meaningful about $\mu(r)$ using this?

If not, what more information is required?

P.S: I have only taken one course in asymptotics in my physics degree (so basically I don't know much) ....