\begin{definition}[Definition:Noncototient]
A '''noncototient''' is a positive integer $n$ such that:
:$\nexists m \in \Z_{>0}: m - \map \phi m = n$
where $\map \phi m$ denotes the Euler $\phi$ function.
That is, a '''noncototient''' is a positive integer which is not the cototient of any positive integer.
\end{definition}