\begin{definition}[Definition:Reverse-and-Add]
Let $m \in \Z_{>0}$ be a positive integer expressed in decimal notation.
Let $r: \Z_{>0} \to \Z_{>0}$ be the mapping defined as:
:For all $n \in \Z_{>0}$: reverse the digits of $m$ and add the result to $m$.
The mapping $r$ is the '''reverse-and-add operation'''.
\end{definition}