\begin{frame} \frametitle{Dependency Pairs} For every $f \in \Sigma$ let $f_\#$ be a fresh symbol with the same arity as $f$.\\ \pause By $t_\#$ we denote $f_\#(t_1,\dots,t_n)$ for $t = f(t_1,\dots,t_n) \in \TTlong$. \pause\medskip \begin{definition}[Dependency Pairs] \centerline{$\DP(R) = \{\ell_\# \to r'_\# \mid \ell \to r \in R,\; r' \trianglelefteq r \text{ with } r' \not\in {\cal X}\}$} \end{definition}\ \\[-.8em] \pause\medskip \begin{example} \vspace{-1em} \begin{align*} R = \{ \; {\rm f}(x) \to {\rm g}({\rm f}(x)) \;\} \end{align*} \pause\vspace{-3em} \begin{align*} \DP(R) = \{\; {\rm f}_\#(x) &\to {\rm g}_\#({\rm f}(x)),\\ {\rm f}_\#(x) &\to {\rm f}_\#(x) \;\} \end{align*} \vspace{-1.5em} \end{example} \end{frame}