An
D995: Integer $a \in \mathbb{Z}$ is a
16-bit integer if and only if
\begin{equation}
\begin{split}
\exists \, r_0, r_1, \ldots, r_{15} \in \{ 0, 1 \} :
a
& = r_0 + 2 r_1 + 4 r_2 + 8 r_3 + 16 r_4 + 32 r_5 + 64 r_6 + 128 r_7 \\
& \quad + 256 r_8 + 512 r_9 + 1024 r_{10} + 2048 r_{11} + 4096 r_{12} \\
& \quad + 8192 r_{13} + 16384 r_{14} - 32768 r_{15}
\end{split}
\end{equation}
