| Résume | The group of transseries of Dulac type is the natural framework to study the asymptotic expansions of germs of first return maps near hyperbolic polycycles in analytic planar vector fields. Motivated by a problem in dynamical systems, we delve into the classification of Dulac type transseries up to conjugation by non-ramified power series. In a joint work with M. Resman, we uncover a quite surprising rigidity phenomenon, demonstrating that formal conjugacy of formal series implies analytic conjugacy of the underlying analytic germs. |
