\begin{tabbing} (\=(((D 5) \+ \\[0ex]CollapseTHEN (Reduce 0))$\cdot$) \\[0ex]CollapseTHEN ((Auto\_aux (first\_nat 1:n \-\\[0ex]) ((first\_nat 1:n),(first\_nat 3:n)) (first\_tok :t) inil\_term)))$\cdot$ \end{tabbing}