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What is the name of a set with empty interior? Wikipedia in a older version, say that is a hollow set, but i think that it is false. It is true? thanks in advance!

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Co-dense, perhaps? – Cameron Buie Jan 15 '13 at 3:33
yes it is true thanks! – Fenrir Jan 15 '13 at 3:38
On behalf of jargon-weary people, I humbly request such sets to be called "sets with empty interior". – user53153 Jan 15 '13 at 3:47
@CameronBuie can you make your comment an answer to accept it? – Fenrir Mar 1 '13 at 2:26
Very well. I shall. – Cameron Buie Mar 1 '13 at 5:50
up vote 6 down vote accepted

I hereby dub such sets: "co-dense."

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This terminology appears in Engelking's General Topology. – arjafi Mar 1 '13 at 5:56
@Arthur: Excellent! I'd have been shocked if I were the first to think of it. – Cameron Buie Mar 1 '13 at 6:04
@CameronBuie thaks! – Fenrir Mar 1 '13 at 22:26

Wikipedia says that "sets with empty interior have been called boundary sets."

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