# Maybe self-destructive

Calculus Level 5

$\large \left (\sum_{x=0}^\infty \dfrac{ (2x)! (5^x + 6^x) }{x!^2 \cdot 30^x } \right )^2$

If the value of the expression above is in the form of $$a + \sqrt b$$, where $$a$$ and $$b$$ are positive integers, find $$a+b$$.

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