Let $X_1, X_2, X_3, \dots \in \text{Bernoulli}(\theta)$ each be a
D207: Bernoulli random boolean number such that
A
D5216: Random natural number $B \in \text{Random}(\mathbb{N})$ is a
binomial random natural number with parameters $N \in \mathbb{N}$ and $\theta$ if and only if
\begin{equation}
B
\overset{d}{=}
\sum_{n = 1}^N X_n
\end{equation}