Theorem 7.4.8. Negative Binomial Limiting Distribution.
For the negative binomial distribution 7.4.2, as \(r \rightarrow \infty\)
\begin{equation*}
\gamma_1 \rightarrow 0
\end{equation*}
and
\begin{equation*}
\gamma_2 \rightarrow 3.
\end{equation*}