This paper is available on arxiv under CC BY-NC-ND 4.0 DEED license.

**Authors:**

(1) U Jin Choi, Department of mathematical science, Korea Advanced Institute of Science and Technology & ujchoi@kaist.ac.kr;

(2) Kyung Soo Rim, Department of mathematics, Sogang University & ksrim@sogang.ac.kr.

## Table of Links

- Introduction
- Organization and notation
- Problem Setting and Preliminaries
- Generalized Wiener algebra and Fréchet derivative
- Characterization of coefficients
- Coefficients from an ergodic process
- Conclusion & References

To state the main theorem of this section we need the following lemma.

This completes the proof.