The spaces of formal power series of class M of Roumieu type and of Beurling type

Abstract

In this article, we introduce the space of formal power series of class $\mathbb M$ of Roumieu (resp., Beurling) type, which is the generalization of the space of entire functions of normal (resp., minimal) type with respect to a proximate order. And we characterize continuous endomorphisms of these spaces.