\begin{tabbing}
lconnects($p$;$i$;$j$)
\\[0ex]$\,\equiv$$_{\mbox{\scriptsize def}}$$\;\;$\=lpath($p$)\+
\\[0ex]\& ($\parallel$$p$$\parallel$ $=$ 0 $\in$ $\mathbb{Z}$ $\Rightarrow$ $i$ $=$ $j$ $\in$ Id)
\\[0ex]\& ($\neg\parallel$$p$$\parallel$ $=$ 0 $\in$ $\mathbb{Z}$ $\Rightarrow$ $i$ $=$ source(hd($p$)) $\in$ Id \& $j$ $=$ destination(last($p$)) $\in$ Id)
\-
\end{tabbing}