[Haskell] Power series in a nutshell

For lovers of things small and beautiful, http://www.cs.dartmouth.edu/~doug/powser.html boils down basic operations on power series with numeric coefficients to the bare minimum--each is a one-liner. Included are overloaded arithmetic operators, integration, differentiation, functional composition, functional inverse and coercion from scalars. --A telling demonstration of the power of lazy evaluation and of Haskell's attunement to math. Doug McIlroy