$\forall$$a$:$\mathbb{N}$, $n$:$\mathbb{N}^{+}$, $p$, $q$:$\mathbb{N}$. Div($a$;$n$;$p$) $\Rightarrow$ Div($a$;$n$;$q$) $\Rightarrow$ ($p$ = $q$ $\in$ $\mathbb{Z}$)