# On Orlicz classes defined in terms of associated weight functions

## TL;DR

This paper explores Orlicz classes using associated weight functions and connects them to weight sequences and dual sequences.

## Contribution

The paper introduces a new characterization of N-functions using weight sequences and links complementary N-functions to dual sequences.

## Key findings

- N-function properties can be characterized using weight sequences, enabling construction of examples.
- A connection is established between complementary N-functions and dual sequences.
- The framework is shown to be meaningful for abstractly given N-functions.

## Abstract

N-functions and their growth and regularity properties are crucial in order to introduce and study Orlicz classes and Orlicz spaces. We consider N-functions which are given in terms of so-called associated weight functions. These functions are frequently appearing in the theory of ultradifferentiable function classes and in this setting additional information is available since associated weight functions are defined in terms of a given weight sequence. We express and characterize several known properties for N-functions purely in terms of weight sequences which allows to construct (counter-) examples. Moreover, we study how for abstractly given N-functions this framework becomes meaningful and finally we establish a connection between the complementary N-function and the recently introduced notion of the so-called dual sequence.