\begin{equation*} \mu = \frac{r}{p} \end{equation*}

\begin{equation*} \sigma^2 = r \frac{1-p}{p^2} \end{equation*}

\begin{equation*} \gamma_1 = \frac{2-p}{\sqrt{r(1-p)}} \end{equation*}

\begin{equation*} \gamma_2 = \frac{p^2-6p+6}{r(1-p)} + 3 \end{equation*}