Let $A = \left\{ \frac { 1967 + 1686 i \sin \theta } { 7 - 3 i \cos \theta } : \theta \in \mathbb { R } \right\}$. If $A$ contains exactly one positive integer $n$, then the value of $n$ is
Let $A = \left\{ \frac { 1967 + 1686 i \sin \theta } { 7 - 3 i \cos \theta } : \theta \in \mathbb { R } \right\}$. If $A$ contains exactly one positive integer $n$, then the value of $n$ is