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Given complement to set $M$ is recursively enumerable and recursive set $R$. What will be the type of the subset of M, elements of which are in R ?

I think they will be also recursively enumerable, but I'm not quite sure about it.

Asaf Karagila
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Kevin
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  • Both $M$ and $R$ are co-recursively enumerable (meaning the complement of $M$ and the complement of $R$ are r.e.). The intersection of two co-r.e. sets is always co-r.e. – realdonaldtrump Aug 03 '18 at 10:41

1 Answers1

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the complement of $M := \Bbb N$ is recursively enumerable; $R := \Bbb N$ is recursive; good luck classifying the subsets of $\Bbb N$.

Kenny Lau
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