====== Order (for Groups) ====== ====Definition==== Let $G$ be a [[definition:group]] with identity $e$, and let $g\in G$. * The $\textdef{order}$ of $G$, denoted $|G|$, is the cardinality of $G$. * The $\textdef{order}$ of $g$, denoted $|g|$, is the smallest positive integer $n$ such that $g^n = e$, if such an $n$ exists. If no such $n$ exists, we say $g$ has infinite order. ---- ==== Remarks ==== * None. ---- ==== $\LaTeX$ version ==== %%%%% % DEPENDENCIES % RequiredMacros: \newcommand{\textdef}[1]{\textit{#1}} %%%%% \begin{definition} Let $G$ be a group with identity $e$, and let $g\in G$. \begin{itemize} \item The \textdef{order} of $G$, denoted $|G|$, is the cardinality of $G$. \item The \textdef{order} of $g$, denoted $|g|$, is the smallest positive integer $n$ such that $g^n = e$, if such an $n$ exists. If no such $n$ exists, $g$ is said to have infinite order. \end{itemize} \end{definition} ---- ==== External links ==== * [[wp>Order (group theory)]] {{tag>definition needsreview rjosh rben}}