[math-fun] how to find sequence associated with dirichlet generating function?

For a standard or exponential generating function, you find the sequence by taking the Taylor series. How does one find the sequence a(n) for a Dirichlet generating function f(s)=sum(n=1 to inf) a(n)/n^s ? -- Mike Stay staym@clear.net.nz http://www.cs.auckland.ac.nz/~msta039