Test this Series for Convergence or Divergence.

Summation from 1 to infinity of (-1)^n * sin(8Pi/n)

It's from the Alternating Series Test section. I wasn't sure how to do this. I compared b(sub n)= sin(8Pi/n) to b(sub n+1)=sin(8Pi/n+1), b(sub n+1) is always less than b(sub n), so I just take the limit of b(sub n), right? If it's 0, it's convergent?

I don't have my book with me so I'm not quite sure.