Infinite sum of Geometric Distribution and Negative Binomial Distribution

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I have the following infinite sum of a geometric and a negative binomial distribution:

$F(x) = \sum_{i=1}^{\infty} Geom(.5, i) NBinom(.5, 3+3i, x - 3+3i)$

I've been able to simplify that down to:

$F(x) = \sum_{i=1}^{\infty} \binom{x-1}{2+3i}0.5^{(i+x)}$

Is there any way to remove the infinite sum from this?