The result is the coefficient of the term $x^{30}$ in the expanded form of the following polynomial $$(1+x+x^2+\cdots)^{50}=\left(\frac{1}{1-x}\right)^{50}=(1-x)^{-50}$$

The generalized binomial theorem gives the answer as $$\binom{-50}{30}(-1)^{30}=\binom{50+30-1}{30}=\boxed{\binom{79}{30}}$$