I have a set $A$ of size $n$.
I have a collection of subsets of $A$ that contains $k>{n\choose n/2} $ elements.
I want to prove that there are two sets $B, C$ in this collection such that $B\subset C$.
Any idea ?
2026-03-26 12:53:59.1774529639
Collection of subsets with more than $n\choose n/2$ elements must have set contained in another
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