Re: countable collection of dense open subsets of reals with intersection having 0 measure

David Belanger wrote:

Am I reading this right? Isn't any dense, open subset of
the reals (and hence a countable intersection) cocountable?

If C is a closed nowhere dense subset of the reals, then
the complement of C is a dense open set. Now note that
C can be uncountable, for example when C is a Cantor set.

Dave L. Renfro
.

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