# Covering Radius of Permutation Groups with Infinity-Norm

## TL;DR

This paper investigates the covering radius of permutation group codes under the infinity-norm, providing exact values for certain groups, bounds for others, and improvements over previous results.

## Contribution

It determines the covering radius of the $(p,q)$-type group, finds the maximum radius under relabeling, and improves bounds for dihedral group codes.

## Key findings

- Exact covering radius for $(p,q)$-type groups.
- Maximum covering radius under conjugation.
- Lower bound for dihedral group code that improves previous bounds.

## Abstract

The covering radius of permutation group codes are studied in this paper with $l_{\infty}$-metric. We determine the covering radius of the $(p,q)$-type group, which is a direct product of two cyclic transitive groups. We also deduce the maximum covering radius among all the relabelings of this group under conjugation, that is, permutation groups with the same algebraic structure but with relabelled members. Finally, we give a lower bound of the covering radius of the dihedral group code, which differs from the trivial upper bound by a constant at most one. This improves the result of Karni and Schwartz in 2018, where the gap between their lower and upper bounds tends to infinity as the code length grows.