Some combinatorial problems in the theory of partial transformation semigroups

Let \(X_n = \{1, 2, \ldots , n\}\). On a partial transformation \(\alpha : \mathop{\rm Dom}\nolimits \alpha \subseteq  X_n \rightarrow \mbox{Im}\,\alpha \subseteq X_n\) of \(X_n\) the following parameters are defined: the  breadth  or  width of \(\alpha\) is \(\mid{\mathop{\rm Dom}\nolimits}\  \alph...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Datum:2018
1. Verfasser: Umar, A.
Format: Artikel
Sprache:Englisch
Veröffentlicht: Lugansk National Taras Shevchenko University 2018
Schlagworte:
Online Zugang:https://admjournal.luguniv.edu.ua/index.php/adm/article/view/1027
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Назва журналу:Algebra and Discrete Mathematics

Institution

Algebra and Discrete Mathematics
_version_ 1856543025731207168
author Umar, A.
author_facet Umar, A.
author_sort Umar, A.
baseUrl_str
collection OJS
datestamp_date 2018-04-26T01:41:11Z
description Let \(X_n = \{1, 2, \ldots , n\}\). On a partial transformation \(\alpha : \mathop{\rm Dom}\nolimits \alpha \subseteq  X_n \rightarrow \mbox{Im}\,\alpha \subseteq X_n\) of \(X_n\) the following parameters are defined: the  breadth  or  width of \(\alpha\) is \(\mid{\mathop{\rm Dom}\nolimits}\  \alpha\mid\), the collapse of \(\alpha\) is \(c(\alpha)=\mid\cup_{t \in \mbox{Im} \alpha}\{t \alpha^{-1}: \mid t\alpha^{-1}\mid \geq 2\}\mid\), fix of \(\alpha\) is \(f(\alpha) = \mid\{x \in X_n: x\alpha = x\}\mid\), the  height of \(\alpha\) is \(\mid\mbox{Im}\,\alpha\mid\), and the right [left] waist of \(\alpha\) is \(\max(\mbox{Im}\,\alpha)\, [\min(\mbox{Im}\,\alpha)]\). The cardinalities of some equivalences defined by equalities of these parameters on \({\cal T}_n\), the semigroup of full transformations of \(X_n\), and \({\cal P}_n\) the semigroup of partial transformations of \(X_n\) and some of their notable subsemigroups that have been computed are gathered together and the open problems highlighted.
first_indexed 2025-12-02T15:38:09Z
format Article
id admjournalluguniveduua-article-1027
institution Algebra and Discrete Mathematics
language English
last_indexed 2025-12-02T15:38:09Z
publishDate 2018
publisher Lugansk National Taras Shevchenko University
record_format ojs
spelling admjournalluguniveduua-article-10272018-04-26T01:41:11Z Some combinatorial problems in the theory of partial transformation semigroups Umar, A. full transformation, partial transformation, breadth, collapse, fix, height and right (left) waist of a transformation. Idempotents and nilpotents 20M17, 20M20, 05A10, 05A15 Let \(X_n = \{1, 2, \ldots , n\}\). On a partial transformation \(\alpha : \mathop{\rm Dom}\nolimits \alpha \subseteq  X_n \rightarrow \mbox{Im}\,\alpha \subseteq X_n\) of \(X_n\) the following parameters are defined: the  breadth  or  width of \(\alpha\) is \(\mid{\mathop{\rm Dom}\nolimits}\  \alpha\mid\), the collapse of \(\alpha\) is \(c(\alpha)=\mid\cup_{t \in \mbox{Im} \alpha}\{t \alpha^{-1}: \mid t\alpha^{-1}\mid \geq 2\}\mid\), fix of \(\alpha\) is \(f(\alpha) = \mid\{x \in X_n: x\alpha = x\}\mid\), the  height of \(\alpha\) is \(\mid\mbox{Im}\,\alpha\mid\), and the right [left] waist of \(\alpha\) is \(\max(\mbox{Im}\,\alpha)\, [\min(\mbox{Im}\,\alpha)]\). The cardinalities of some equivalences defined by equalities of these parameters on \({\cal T}_n\), the semigroup of full transformations of \(X_n\), and \({\cal P}_n\) the semigroup of partial transformations of \(X_n\) and some of their notable subsemigroups that have been computed are gathered together and the open problems highlighted. Lugansk National Taras Shevchenko University 2018-04-26 Article Article Peer-reviewed Article application/pdf https://admjournal.luguniv.edu.ua/index.php/adm/article/view/1027 Algebra and Discrete Mathematics; Vol 17, No 1 (2014) 2415-721X 1726-3255 en https://admjournal.luguniv.edu.ua/index.php/adm/article/view/1027/551 Copyright (c) 2018 Algebra and Discrete Mathematics
spellingShingle full transformation
partial transformation
breadth
collapse
fix
height and right (left) waist of a transformation. Idempotents and nilpotents
20M17
20M20
05A10
05A15
Umar, A.
Some combinatorial problems in the theory of partial transformation semigroups
title Some combinatorial problems in the theory of partial transformation semigroups
title_full Some combinatorial problems in the theory of partial transformation semigroups
title_fullStr Some combinatorial problems in the theory of partial transformation semigroups
title_full_unstemmed Some combinatorial problems in the theory of partial transformation semigroups
title_short Some combinatorial problems in the theory of partial transformation semigroups
title_sort some combinatorial problems in the theory of partial transformation semigroups
topic full transformation
partial transformation
breadth
collapse
fix
height and right (left) waist of a transformation. Idempotents and nilpotents
20M17
20M20
05A10
05A15
topic_facet full transformation
partial transformation
breadth
collapse
fix
height and right (left) waist of a transformation. Idempotents and nilpotents
20M17
20M20
05A10
05A15
url https://admjournal.luguniv.edu.ua/index.php/adm/article/view/1027
work_keys_str_mv AT umara somecombinatorialproblemsinthetheoryofpartialtransformationsemigroups