Let $F$ be a $n-$element set, where $n$ is finite, and every $r$ subsets intersect. How can I prove that $$|F| \leq {n \choose k} - {n - r + 1 \choose k}$$?
2026-03-27 06:09:53.1774591793
Erdos-Ko-Rado Theorem for $r$ subsets
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