# Sum up the series!

Probability Level 4

$1 + \frac{1}{3} + \frac{1\cdot 3}{3\cdot 6} + \frac{1\cdot 3\cdot 5}{3\cdot 6\cdot 9} + \cdots = \sqrt{Y}$

$Y$ is given as above, find $5Y + 1$.

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