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\begin{frame}
\frametitle{Infinite Terms}

\begin{center}
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\begin{definition}
An \alert{infinite term} is a partial map $t : \NN^* \pto \Sigma$ from positions to symbols such that:
\begin{itemize}
\item $t(\epsilon) \in \Sigma$, and
\item $t(i p) \in \Sigma \Longleftrightarrow 1 \le i \le \arity{t(p)}$
\end{itemize}
\pause
The \alert{set of finite and infinite terms} is denoted by $\iter$.
\end{definition}
\end{frame}