$S$-preclones and the Galois connection ${}^S\mathrm{Pol}$-${}^S\mathrm{Inv}$, Part I
Abstract
We consider -operations in which each argument is assigned a signum representing a "property" such as being order-preserving or order-reversing with respect to a fixed partial order on . The set of such properties is assumed to have a monoid structure reflecting the behaviour of these properties under the composition of -operations (e.g., order-reversing composed with order-reversing is order-preserving). The collection of all -operations with prescribed properties for their signed arguments is not a clone (since it is not closed under arbitrary identification of arguments), but it is a preclone with special properties, which leads to the notion of -preclone. We introduce -relations , -relational clones, and a preservation property (), and we consider the induced Galois connection -. The -preclones and -relational clones turn out to be exactly the closed sets of this Galois connection. We also establish some basic facts about the structure of the lattice of all -preclones on .
Cite
@article{arxiv.2306.00493,
title = {$S$-preclones and the Galois connection ${}^S\mathrm{Pol}$-${}^S\mathrm{Inv}$, Part I},
author = {Peter Jipsen and Erkko Lehtonen and Reinhard Pöschel},
journal= {arXiv preprint arXiv:2306.00493},
year = {2024}
}
Comments
33 pages