\begin{tabbing} (\=(InstLemma `mul\_preserves\_le` [$b$;$a$;$n$]) \+ \\[0ex]CollapseTHEN ((Auto\_aux (first\_nat 1:n \-\\[0ex]) ((first\_nat 2:n),(first\_nat 3:n)) (first\_tok :t) inil\_term)))$\cdot$ \end{tabbing}