Empty set
From AoPSWiki
The empty set (generally denoted 
or 
) is the (unique) set containing no elements. It is therefore a subset of every set.
This article is a stub. Help us out by expanding it.
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The empty set (generally denoted or ) is the (unique) set containing no elements. It is therefore a subset of every set.
This article is a stub. Help us out by expanding it.
