Dice Question Streamline Icon: https://streamlinehq.com

Noether number inequality for all finite groups

Establish whether, for every finite group G, the inequality d(G) + 1 ≤ β(G) holds, where d(G) denotes the small Davenport constant and β(G) denotes the Noether number of G.

Information Square Streamline Icon: https://streamlinehq.com

Background

The paper discusses connections between the Davenport constants and invariant theory. For abelian groups, Schmid proved the equality d(G) + 1 = β(G). Cziszter and Domokos extended this by proving d(G) + 1 ≤ β(G) for groups having a cyclic subgroup of index 2. The authors point out that it remains unresolved whether this inequality extends to all finite groups.

This question ties the combinatorial invariant d(G) to the invariant-theoretic quantity β(G) and seeks a general principle valid across all finite groups.

References

Then, Schmid showed that $\mathsf d (G) + 1 = \boldsymbol{\beta} (G)$ for all abelian groups $G$, and in , Cziszter and Domokos showed that $\mathsf d (G) + 1 \le \boldsymbol{\beta} (G)$ for groups $G$ with a cyclic subgroup of index $2$. It is still an open question whether the inequality holds true for all finite groups.

A classification of finite groups with small Davenport constant (2409.00363 - Oh, 31 Aug 2024) in Section 1 (Introduction)