How can I show that $3281$ is a strong pseudoprime to base $3$?
My attempt: $3^d≡1$ mod $3281$, which is true for $d=16k$ and $3281=17\cdot193$. Hence $3281$ is a strong pseudoprime to base $3$.
Does this solution confirm to the definition: https://en.wikipedia.org/wiki/Strong_pseudoprime ?