English

A ridiculously simple and explicit implicit function theorem

Complex Variables 2009-11-16 v1 Combinatorics

Abstract

I show that the general implicit-function problem (or parametrized fixed-point problem) in one complex variable has an explicit series solution given by a trivial generalization of the Lagrange inversion formula. I give versions of this formula for both analytic functions and formal power series.

Keywords

Cite

@article{arxiv.0902.0069,
  title  = {A ridiculously simple and explicit implicit function theorem},
  author = {Alan D. Sokal},
  journal= {arXiv preprint arXiv:0902.0069},
  year   = {2009}
}
R2 v1 2026-06-21T12:06:39.217Z