# Omg So much big series!

Calculus Level 3

$\large \displaystyle \lim_{x \to -1} \dfrac{(1+x)(1-x^2)(1+x^3)(1-x^4) \cdots (1-x^{4n})}{[(1+x)(1-x^2)(1+x^3)(1-x^4) \cdots (1-x^{2n})]^{2}}$

If the limit above can be expressed in the form $$\dbinom{pn}{qn}$$ for positive integers $$p,q,n$$, find the value of $$p + q$$.

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