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This is collection of issues that need to be resolved before a release. The goal is to adjust the WreathProduct interface for the GAP 4.12 release and the internal code in this package. Most potential for discussion arise in the files `WreathProductElements.gi` and `WreathProductElements.gd`. Most difficulties arise from the fact, that WreathProducts were already implemented in GAP and did not provide the neccessary interface for this packge. The package implementation started before we added the methods `WreathProductElementList` and `ListWreathProductElement` into GAP lib. Theoretical Background (brief): The work is based on the recent paper [Conjugacy classes and centralisers in wreath products](https://arxiv.org/abs/2107.04645) by Dominik Bernhardt, Alice C. Niemeyer, Friedrich Rober (me) and Lucas Wollenhaupt. Currently supported operations are `RepresentativeAction` , `ConjugacyClasses` and `Centraliser` for elements of wreath products. The main idea is to compute a wreath cycle decomposition of elements and to reduce problems onto the base and top component groups of the wreath product. The basic data strucutre needed for the above operations and elements `(f,h)` of a wreath product `K wr H`, where `H < Sym(Γ)` is computed as follows: 1. Compute "wreath cycle decomposition" (runtime `O(|Γ|)`) 3. Solve conjugacy problems in `K` in order to determine the "territory partition" of `Γ`, named `P` (runtime at most `O(|Γ|)` `K`-conjugacy problems, in practice much less) 3. Compute Centraliser of `h` in `H`, named `C` 4. Compute Stabiliser of `P` in `C` (Please note, that I did not implement any new datastructures and have not provided any interface to them. They are currently hidden away in the internal code.)
No due date•7/7 issues closed