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{\bf Boris Bukh}
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{\bf Set Families with a Forbidden Subposet}
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We asymptotically determine the size of the largest family $\cal F$ of
subsets of $\{1,\dots,n\}$ not containing a given poset $P$ if the
Hasse diagram of $P$ is a tree. This is a qualitative generalization
of several known results including Sperner's theorem.

\bye

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