Mathematical Structures: Cancellative semigroups

# Cancellative semigroups

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 %%run pdflatex % \documentclass[12pt]{amsart} \usepackage[pdfpagemode=Fullscreen,pdfstartview=FitBH]{hyperref} \parindent=0pt \parskip=5pt \addtolength{\oddsidemargin}{-.5in} \addtolength{\evensidemargin}{-.5in} \addtolength{\textwidth}{1in} \theoremstyle{definition} \newtheorem{definition}{Definition} \newtheorem*{morphisms}{Morphisms} \newtheorem*{basic_results}{Basic Results} \newtheorem*{examples}{Examples} \newtheorem{example}{} \newtheorem*{properties}{Properties} \newtheorem*{finite_members}{Finite Members} \newtheorem*{subclasses}{Subclasses} \newtheorem*{superclasses}{Superclasses} \newcommand{\abbreviation}[1]{\textbf{Abbreviation: #1}} \pagestyle{myheadings}\thispagestyle{myheadings} \markboth{\today}{math.chapman.edu/structures} \begin{document} \textbf{\Large Cancellative semigroups} \quad\href{http://math.chapman.edu/cgi-bin/structures?action=edit;id=Cancellative_semigroups}{edit} \abbreviation{CanSgrp} \begin{definition} A \emph{cancellative semigroup} is a semigroup $\mathbf{S}=\langle S,\cdot \rangle$ such that $\cdot$ is left cancellative: $z\cdot x=z\cdot y\implies x=y$ $\cdot$ is right cancellative: $x\cdot z=y\cdot z\implies x=y$ \end{definition} \begin{morphisms} Let $\mathbf{S}$ and $\mathbf{T}$ be cancellative semigroups. A morphism from $\mathbf{S}$ to $\mathbf{T}$ is a function $h:S\rightarrow T$ that is a homomorphism: $h(xy)=h(x)h(y)$ \end{morphisms} \begin{basic_results} \end{basic_results} \begin{examples} \begin{example} $\langle \mathbb{N},+\rangle$, the natural numbers, with additition. \end{example} \end{examples} \begin{table}[h] \begin{properties} (\href{http://math.chapman.edu/cgi-bin/structures?Properties}{description}) \begin{tabular}{|ll|}\hline Classtype & Quasivariety\\\hline Equational theory & \\\hline Quasiequational theory & \\\hline First-order theory & \\\hline Locally finite & No\\\hline Residual size & \\\hline Congruence distributive & No\\\hline Congruence modular & No\\\hline Congruence n-permutable & No\\\hline Congruence regular & No\\\hline Congruence uniform & No\\\hline Congruence extension property & \\\hline Definable principal congruences & \\\hline Equationally def. pr. cong. & No\\\hline Amalgamation property & No\\\hline Strong amalgamation property & No\\\hline Epimorphisms are surjective & No\\\hline \end{tabular} \end{properties} \end{table} \begin{finite_members} $f(n)=$ number of members of size $n$. $\begin{array}{lr} f(1)= &1\\ f(2)= &\\ f(3)= &\\ f(4)= &\\ f(5)= &\\ f(6)= &\\ f(7)= &\\ \end{array}$ \end{finite_members} \hyperbaseurl{http://math.chapman.edu/structures/files/} \parskip0pt \begin{subclasses}\ \href{Cancellative_monoids.pdf}{Cancellative monoids} \end{subclasses} \begin{superclasses}\ \href{Semigroups.pdf}{Semigroups} \end{superclasses} \begin{thebibliography}{10} \bibitem{Ln19xx} \end{thebibliography} \end{document} %
 %%run pdflatex % \documentclass[12pt]{amsart} \usepackage[pdfpagemode=Fullscreen,pdfstartview=FitBH]{hyperref} \parindent=0pt \parskip=5pt \addtolength{\oddsidemargin}{-.5in} \addtolength{\evensidemargin}{-.5in} \addtolength{\textwidth}{1in} \theoremstyle{definition} \newtheorem{definition}{Definition} \newtheorem*{morphisms}{Morphisms} \newtheorem*{basic_results}{Basic Results} \newtheorem*{examples}{Examples} \newtheorem{example}{} \newtheorem*{properties}{Properties} \newtheorem*{finite_members}{Finite Members} \newtheorem*{subclasses}{Subclasses} \newtheorem*{superclasses}{Superclasses} \newcommand{\abbreviation}[1]{\textbf{Abbreviation: #1}} \pagestyle{myheadings}\thispagestyle{myheadings} \markboth{\today}{math.chapman.edu/structures} \begin{document} \textbf{\Large Cancellative semigroups} \quad\href{http://math.chapman.edu/cgi-bin/structures?action=edit;id=Cancellative_semigroups}{edit} \abbreviation{CanSgrp} \begin{definition} A \emph{cancellative semigroup} is a \href{Semigroups.pdf}{semigroup} $\mathbf{S}=\langle S,\cdot\rangle$ such that $\cdot$ is left cancellative: $z\cdot x=z\cdot y\implies x=y$ $\cdot$ is right cancellative: $x\cdot z=y\cdot z\implies x=y$ \end{definition} \begin{morphisms} Let $\mathbf{S}$ and $\mathbf{T}$ be cancellative semigroups. A morphism from $\mathbf{S}$ to $\mathbf{T}$ is a function $h:S\rightarrow T$ that is a homomorphism: $h(xy)=h(x)h(y)$ \end{morphisms} \begin{basic_results} \end{basic_results} \begin{examples} \begin{example} $\langle \mathbb{N},+\rangle$, the natural numbers, with additition. \end{example} \end{examples} \begin{table}[h] \begin{properties} (\href{http://math.chapman.edu/cgi-bin/structures?Properties}{description}) \begin{tabular}{|ll|}\hline Classtype & quasivariety\\\hline Equational theory & \\\hline Quasiequational theory & \\\hline First-order theory & \\\hline Locally finite & no\\\hline Residual size & \\\hline Congruence distributive & no\\\hline Congruence modular & no\\\hline Congruence n-permutable & no\\\hline Congruence regular & no\\\hline Congruence uniform & no\\\hline Congruence extension property & \\\hline Definable principal congruences & \\\hline Equationally def. pr. cong. & no\\\hline Amalgamation property & no\\\hline Strong amalgamation property & no\\\hline Epimorphisms are surjective & no\\\hline \end{tabular} \end{properties} \end{table} \begin{finite_members} $f(n)=$ number of members of size $n$. $\begin{array}{lr} f(1)= &1\\ f(2)= &\\ f(3)= &\\ f(4)= &\\ f(5)= &\\ f(6)= &\\ f(7)= &\\ \end{array}$ \end{finite_members} \hyperbaseurl{http://math.chapman.edu/structures/files/} \begin{subclasses}\ \href{Cancellative_monoids.pdf}{Cancellative monoids} \end{subclasses} \begin{superclasses}\ \href{Semigroups.pdf}{Semigroups} \end{superclasses} \begin{thebibliography}{10} \bibitem{Ln19xx} \end{thebibliography} \end{document} %

http://mathcs.chapman.edu/structuresold/files/Cancellative_semigroups.pdf
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\documentclass[12pt]{amsart}
\usepackage[pdfpagemode=Fullscreen,pdfstartview=FitBH]{hyperref}
\parindent=0pt
\parskip=5pt
\theoremstyle{definition}
\newtheorem{definition}{Definition}
\newtheorem*{morphisms}{Morphisms}
\newtheorem*{basic_results}{Basic Results}
\newtheorem*{examples}{Examples}
\newtheorem{example}{}
\newtheorem*{properties}{Properties}
\newtheorem*{finite_members}{Finite Members}
\newtheorem*{subclasses}{Subclasses}
\newtheorem*{superclasses}{Superclasses}
\newcommand{\abbreviation}[1]{\textbf{Abbreviation: #1}}
\markboth{\today}{math.chapman.edu/structures}

\begin{document}
\textbf{\Large Cancellative semigroups}

\abbreviation{CanSgrp}
\begin{definition}
A \emph{cancellative semigroup} is a \href{Semigroups.pdf}{semigroup} $\mathbf{S}=\langle S,\cdot\rangle$ such that

$\cdot$ is left cancellative:  $z\cdot x=z\cdot y\implies x=y$

$\cdot$ is right cancellative:  $x\cdot z=y\cdot z\implies x=y$
\end{definition}

\begin{morphisms}
Let $\mathbf{S}$ and $\mathbf{T}$ be cancellative semigroups. A morphism from
$\mathbf{S}$ to $\mathbf{T}$ is a function $h:S\rightarrow T$ that is a
homomorphism:

$h(xy)=h(x)h(y)$
\end{morphisms}

\begin{basic_results}
\end{basic_results}

\begin{examples}
\begin{example}
$\langle \mathbb{N},+\rangle$, the natural numbers, with additition.
\end{example}
\end{examples}

\begin{table}[h]
\begin{properties} (\href{http://math.chapman.edu/cgi-bin/structures?Properties}{description})

\begin{tabular}{|ll|}\hline
Classtype & quasivariety\\\hline
Equational theory & \\\hline
Quasiequational theory & \\\hline
First-order theory & \\\hline
Locally finite & no\\\hline
Residual size & \\\hline
Congruence distributive & no\\\hline
Congruence modular & no\\\hline
Congruence n-permutable & no\\\hline
Congruence regular & no\\\hline
Congruence uniform & no\\\hline
Congruence extension property & \\\hline
Definable principal congruences & \\\hline
Equationally def. pr. cong. & no\\\hline
Amalgamation property & no\\\hline
Strong amalgamation property & no\\\hline
Epimorphisms are surjective & no\\\hline
\end{tabular}
\end{properties}
\end{table}

\begin{finite_members} $f(n)=$ number of members of size $n$.

$\begin{array}{lr} f(1)= &1\\ f(2)= &\\ f(3)= &\\ f(4)= &\\ f(5)= &\\ f(6)= &\\ f(7)= &\\ \end{array}$
\end{finite_members}

\hyperbaseurl{http://math.chapman.edu/structures/files/}
\begin{subclasses}\

\href{Cancellative_monoids.pdf}{Cancellative monoids}

\end{subclasses}
\begin{superclasses}\

\href{Semigroups.pdf}{Semigroups}

\end{superclasses}

\begin{thebibliography}{10}

\bibitem{Ln19xx}

\end{thebibliography}

\end{document}
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