Some combinatorial problems in the theory of symmetric inverse semigroups

Let \(X_n = \{1, 2, \cdots , n\}\) and let \(\alpha : \mathop{\rm Dom}\nolimits \alpha \subseteq  X_n \rightarrow \mathop{\rm Im}\nolimits \alpha \subseteq X_n\) be a (partial) transformation on \(X_n\). On a partial one-one mapping of \(X_n\) the following parameters are defined: the height of \(\a...

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Date:2018
Main Author: Umar, A.
Format: Article
Language:English
Published: Lugansk National Taras Shevchenko University 2018
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Online Access:https://admjournal.luguniv.edu.ua/index.php/adm/article/view/635
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Journal Title:Algebra and Discrete Mathematics

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Algebra and Discrete Mathematics
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author Umar, A.
author_facet Umar, A.
author_sort Umar, A.
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datestamp_date 2018-04-04T09:11:25Z
description Let \(X_n = \{1, 2, \cdots , n\}\) and let \(\alpha : \mathop{\rm Dom}\nolimits \alpha \subseteq  X_n \rightarrow \mathop{\rm Im}\nolimits \alpha \subseteq X_n\) be a (partial) transformation on \(X_n\). On a partial one-one mapping of \(X_n\) the following parameters are defined: the height of \(\alpha\) is  \(h(\alpha)=|\mathop{\rm Im}\nolimits \alpha|\), the right [left] waist of \(\alpha\) is \(w^+(\alpha) = \max(\mathop{\rm Im}\nolimits \alpha)[w^-(\alpha) = \min(\mathop{\rm Im}\nolimits \alpha)]\),  and fix of \(\alpha\) is denoted by \(f(\alpha)\), and defined by \(f(\alpha) = |\{x \in X_n: x\alpha = x\} |\). The cardinalities of some equivalences defined by equalities of these parameters on \(\mathcal{I}_n\), the semigroup of partial one-one mappings of \(X_n\), and some of its notable subsemigroups that have been computed are gathered together and the open problems highlighted.
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spelling admjournalluguniveduua-article-6352018-04-04T09:11:25Z Some combinatorial problems in the theory of symmetric inverse semigroups Umar, A. partial one-one transformation, height, right (left) waist and fix of a transformation. Idempotents and nilpotents 20M18, 20M20, 05A10, 05A15 Let \(X_n = \{1, 2, \cdots , n\}\) and let \(\alpha : \mathop{\rm Dom}\nolimits \alpha \subseteq  X_n \rightarrow \mathop{\rm Im}\nolimits \alpha \subseteq X_n\) be a (partial) transformation on \(X_n\). On a partial one-one mapping of \(X_n\) the following parameters are defined: the height of \(\alpha\) is  \(h(\alpha)=|\mathop{\rm Im}\nolimits \alpha|\), the right [left] waist of \(\alpha\) is \(w^+(\alpha) = \max(\mathop{\rm Im}\nolimits \alpha)[w^-(\alpha) = \min(\mathop{\rm Im}\nolimits \alpha)]\),  and fix of \(\alpha\) is denoted by \(f(\alpha)\), and defined by \(f(\alpha) = |\{x \in X_n: x\alpha = x\} |\). The cardinalities of some equivalences defined by equalities of these parameters on \(\mathcal{I}_n\), the semigroup of partial one-one mappings of \(X_n\), and some of its notable subsemigroups that have been computed are gathered together and the open problems highlighted. Lugansk National Taras Shevchenko University 2018-04-04 Article Article Peer-reviewed Article application/pdf https://admjournal.luguniv.edu.ua/index.php/adm/article/view/635 Algebra and Discrete Mathematics; Vol 9, No 2 (2010) 2415-721X 1726-3255 en https://admjournal.luguniv.edu.ua/index.php/adm/article/view/635/169 Copyright (c) 2018 Algebra and Discrete Mathematics
spellingShingle partial one-one transformation
height
right (left) waist and fix of a transformation. Idempotents and nilpotents
20M18
20M20
05A10
05A15
Umar, A.
Some combinatorial problems in the theory of symmetric inverse semigroups
title Some combinatorial problems in the theory of symmetric inverse semigroups
title_full Some combinatorial problems in the theory of symmetric inverse semigroups
title_fullStr Some combinatorial problems in the theory of symmetric inverse semigroups
title_full_unstemmed Some combinatorial problems in the theory of symmetric inverse semigroups
title_short Some combinatorial problems in the theory of symmetric inverse semigroups
title_sort some combinatorial problems in the theory of symmetric inverse semigroups
topic partial one-one transformation
height
right (left) waist and fix of a transformation. Idempotents and nilpotents
20M18
20M20
05A10
05A15
topic_facet partial one-one transformation
height
right (left) waist and fix of a transformation. Idempotents and nilpotents
20M18
20M20
05A10
05A15
url https://admjournal.luguniv.edu.ua/index.php/adm/article/view/635
work_keys_str_mv AT umara somecombinatorialproblemsinthetheoryofsymmetricinversesemigroups