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arXiv · 2605.12342

Groups of permutations that are even on maximal proper subsets, and related monoids

Vítor H. Fernandes
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Abstract

Let $n$ be a positive integer and let $[n]=\{1,2,\ldots,n\}$. Let $\Gamma_n$ denote the group of permutations on $[n]$ whose restrictions to maximal proper subsets of $[n]$ are even, let $\Sigma_n$ denote the monoid of transformations on $[n]$ whose injective restrictions to maximal proper subsets of $[n]$ are even and let $\Delta_n$ denote the submonoid of $\Sigma_n$ generated by transformations of rank at least $n-1$. In this paper, we present descriptions of $\Gamma_n$, $\Delta_n$ and $\Sigma_n$, determine their cardinalities and ranks, and provide minimal generating sets for each of them.

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Vítor H. Fernandes. 2026-05-12. Groups of permutations that are even on maximal proper subsets, and related monoids. https://arxiv.org/abs/2605.12342

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