Permutation automorphism groups of cyclic codes I: cyclotomic association schemes
Abstract
The Berger-Charpin conjecture predicts that the permutation automorphism group of a cyclic code is generally the q-affine group, which is generated by the shift and the Frobenius multiplier on the index set. The word {\em generally} is not made precise in the literature, and the goal of this series of papers is to study when the Berger-Charpin conjecture or its variants hold. In this first part, we establish a natural connection between the theory of cyclic codes and the theory of cyclotomic association schemes (equivalently, Schur rings over cyclic groups). Using it, we show that the q-affine group is not the correct group to expect for certain code lengths. We characterize these lengths by an arithmetic condition, and show that they have density zero.
Related
- Cyclotomic factorization and fixed-point insertion in colored permutation groups
- The permutation and automorphism groups of univariate multiplicity codes
- On the lengths of MDS codes with a two-transitive permutation automorphism group
- Mathieu groups as flag-transitive automorphism groups of block designs
- p-class groups in the cyclotomic ℤp-extension of imaginary quadratic fields
BibTeX
@misc{wu2026permutation,
title = {{Permutation automorphism groups of cyclic codes I: cyclotomic association schemes}},
author = {Yanni Wu and Ziqing Xiang},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.33050},
eprint = {2609.33050},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.33050},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Permutation automorphism groups of cyclic codes I: cyclotomic association schemes
AU - Yanni Wu
AU - Ziqing Xiang
PY - 2026
DA - 2026/09/27
PB - arXiv
DO - 10.48550/arxiv.2609.33050
UR - https://arxiv.org/abs/2609.33050
AB - The Berger-Charpin conjecture predicts that the permutation automorphism group of a cyclic code is generally the q-affine group, which is generated by the shift and the Frobenius multiplier on the index set. The word {\em generally} is not made precise in the literature, and the goal of this series of papers is to study when the Berger-Charpin conjecture or its variants hold. In this first part, we establish a natural connection between the theory of cyclic codes and the theory of cyclotomic association schemes (equivalently, Schur rings over cyclic groups). Using it, we show that the q-affine group is not the correct group to expect for certain code lengths. We characterize these lengths by an arithmetic condition, and show that they have density zero.
ER -