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random{-}seq($T$;${\it sz}$;${\it eq}$;$f$)
\\[0ex]$\,\equiv$$_{\mbox{\scriptsize def}}$$\;\;$\=$\forall$$k$:$\mathbb{N}$, $g$:(\{0..$k$$^{-}$\}$\rightarrow\mathbb{N}$), $x$:($k$:$\mathbb{N}\times$(\{0..$k$$^{-}$\}$\rightarrow$$T$)).\+
\\[0ex]increasing($g$;$k$) $\Rightarrow$ frequency(eq\_seq(${\it eq}$);derived{-}seq($f$;$\langle$$k$$,\,$$g$$\rangle$);$x$;1;exp(${\it sz}$;$k$))
\-
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