[Haskell] Power series in a nutshell

[Doug McIlroy]

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