\begin{tabbing}
(\=(ReplaceWith $\forall$$x$, $y$:$T$. \{$R$($x$,$y$) $\Rightarrow$ ${\it R'}$($x$,$y$)\} 4) \+
\\[0ex]CollapseTHENA (((Unfold `guard` 0) 
\\[0ex]
\\[0ex]CollapseTHEN ((Auto\_aux (first\_nat 1:n) ((first\_nat 1:n),(first\_nat 4:n)) (first\_tok :t
\-\\[0ex]) inil\_term)))$\cdot$))$\cdot$
\end{tabbing}