# One of those...

$\large A = \frac{\binom{2n + 1}{n + 1}}{\binom{2n - 1}{n}}$ has a closed form if $$n \in \mathbb{Z}^+$$. Find this closed form, and give the value of $$\large A$$ if $$n = 10^9$$. Give your answer to 6 decimal places

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