Abstract
In this paper, we study partial automorphisms and, more generally, injective partial endomorphisms of a finite undirected path from Semigroup Theory perspective. Our main objective is to give formulas for the ranks of the monoids \(\mathrm {IEnd}(P_n)\) and \(\mathrm {PAut}(P_n)\) of all injective partial endomorphisms and of all partial automorphisms of the undirected path \(P_n\) with n vertices. We also describe Green’s relations of \(\mathrm {PAut}(P_n)\) and \(\mathrm {IEnd}(P_n)\) and calculate their cardinals.
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This work was produced, in part, during the visit of the first and third authors to CMA, FCT NOVA, Lisbon, in July 2019. The first author was supported by CMA through a visiting researcher fellowship.
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Communicated by László Márki.
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This work is funded by national funds through the FCT – Fundação para a Ciência e a Tecnologia, I.P., under the scope of the project UIDB/00297/2020 (Center for Mathematics and Applications).
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Dimitrova, I., Fernandes, V.H., Koppitz, J. et al. Partial automorphisms and injective partial endomorphisms of a finite undirected path. Semigroup Forum 103, 87–105 (2021). https://doi.org/10.1007/s00233-021-10193-y
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DOI: https://doi.org/10.1007/s00233-021-10193-y