\begin{tabbing}
((\=ReplaceWithEqv (TryC (HigherC IntSimpC)) \+
\\[0ex](({-}($a$ $\ast$ $b$)) $>$ ({-}0))
\-\\[0ex]$\Leftarrow\!$\=$=$\=$\Rightarrow$ (((({-}$a$) $>$ ({-}0)) \& ($b$ $>$ 0)) $\vee$ ((({-}$a$) $<$ ({-}0)) \& ($b$ $<$ 0))) \+\+
\\[0ex]3) 
\-\\[0ex]CollapseTHENA (
\-\\[0ex](Auto\_aux (first\_nat 1:n) ((first\_nat 1:n),(first\_nat 3:n)) (first\_tok :t) inil\_term)))$\cdot$
\end{tabbing}