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\subsection*{Answer}

Let $s_{1} -> s_{2} -> \cdots$ be an infinite behavior satisfying
$A$'s behavior specification.  For any variable $v$ of $A$,
define $\ov{v}$ to equal $e_{v}(n)$, where $e_{v}(i)$ is the value
of $v$ in state $s_{i}$, for any positive integer $i$.

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