# Is this enough information?

Calculus Level 5

$\Gamma{\left(\dfrac{1}{2}\right)} = \sqrt{\pi}$

Using the fact above, find $$n$$ if $$\dfrac{2^{n-1}(2n-1)}{\sqrt{\pi}}\Gamma{\left(\dfrac{2n-1}{2}\right)} = 9999!!$$.


Notation: $$!!$$ denotes the double factorial notation. For example, $$10!!=10\times8\times6\times4\times2$$.

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