Let $n \in \mathbb{N}$ be a D996: Natural number.
The central binomial coefficient with respect to $n$ is the D996: Natural number $$\begin{equation} \binom{2 n}{n} = \# \left\{ E \subseteq \{ 1, \ldots, 2 n \} : |E| = n \right\} \end{equation}$$