($\lambda$$g$,$p$,$q$,$E$,$z$. $\Pi$ $p$ $\leq$ $i$ $<$ $q$. $E$($i$)) $\in$ $g$:IMonoid$\rightarrow$$p$,$q$:$\mathbb{Z}\rightarrow$(\{$p$..$q$$^{-}$\}$\rightarrow\mid$$g$$\mid$)$\rightarrow$($\downarrow$True)$\rightarrow\mid$$g$$\mid$