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$\vdash$  \=$\forall$$T$:Type, $n$, $m$:$\mathbb{N}$, $b$:$T$, $c$:(\{0..($n$+$m$)$^{-}$\}$\rightarrow$$T$$\rightarrow$$T$).\+
\\[0ex]primrec($n$+$m$;$b$;$c$) = primrec($n$;primrec($m$;$b$;$c$);$\lambda$$i$,$t$. $c$($i$+$m$,$t$))
\-
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