[math-fun] Inverse function of error function

If x=erf(y), then say y=erfinv(x). SMP jocks: What is the Maclaurin series of erfinv(x)? Obviously the erfinv function is useful for statistics. It also occurs to me: This series should have infinite radius of convergence, i.e. erfinv(x) should be a very well behaved "entire" function. Because: the derivative of erf is never zero anywhere in the complex plane, and the value of erf is always finite everywhere in the plane, so its inverse function should exist everywhere.