Generators and presentations for direct and wreath products of monoid acts
Abstract
We investigate the preservation of the properties of being finitely generated and finitely presented under both direct and wreath products of monoid acts. A monoid M is said to preserve property P in direct products if, for any two M-acts A and B, the direct product A x B has property P if and only if both A and B have property P. It is proved that the monoids M that preserve finite generation (resp. finitely presentability) in direct products are precisely those for which the diagonal M-act M x M is finitely generated (resp. finitely presented). We show that a wreath product A ≀ B is finitely generated if and only if both A and B are finitely generated. It is also proved that a necessary condition for A ≀ B to be finitely presented is that both A and B are finitely presented. Finally, we find some sufficient conditions for a wreath product to be finitely presented.
Citation
Miller , C 2018 , ' Generators and presentations for direct and wreath products of monoid acts ' , Semigroup Forum , vol. First Online . https://doi.org/10.1007/s00233-018-9987-5
Publication
Semigroup Forum
Status
Peer reviewed
ISSN
0037-1912Type
Journal article
Rights
© The Author(s) 2018. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.
Description
The author would like to thank the EPSRC for financial support.Collections
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