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atoms{-}distinct(${\it tab}$)
\\[0ex]$\,\equiv$$_{\mbox{\scriptsize def}}$$\;\;$\=$\forall$$i$:\{0..$\parallel$${\it tab}$$\parallel$ $^{-}$\}, $j$:\{0..$\parallel$${\it tab}$$\parallel$ $^{-}$\}.\+
\\[0ex]st{-}atom(${\it tab}$;$i$) $=$ st{-}atom(${\it tab}$;$j$) $\in$ Atom1 $\Rightarrow$ $i$ $=$ $j$ $\in$ $\mathbb{Z}$
\-
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