\begin{tabbing} (\=(((((Unfold `refl` 0) \+ \\[0ex]CollapseTHENM (GenRepD))$\cdot$) \\[0ex]CollapseTHENM (HypBackchain))$\cdot$) \\[0ex] \\[0ex]CollapseTHENA ((Auto\_aux (first\_nat 1:n) ((first\_nat 1:n),(first\_nat 3:n)) (first\_tok :t \-\\[0ex]) inil\_term)))$\cdot$ \end{tabbing}