How to find $\sum_{n=1}^{\infty}{\binom{2n-1}{n} x^n}, |x| < \frac{1}{4} ?$

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I have tried to find a differential equation for such $S(x)$ but I could not. I also tried to express it in binomial form but I could not.

I was finding expected value of some other problem when I got this. So, I don't know if it has a closed form.

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HINT:

$$\binom{2n-1}{n}=\frac12 \binom{2n}{n}$$

Now, look at the series expansion of $(1-t)^{-1/2}$.