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تسجيل مستخدم جديدNote: Union-closed families with small average overlap densities
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تأليف
David Ellis
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In this very short note, we point out that the average overlap density of a union-closed family $mathcal{F}$ of subsets of ${1,2,ldots,n}$ may be as small as $Theta((log log |mathcal{F}|)/(log |mathcal{F}|))$, for infinitely many positive integers $n$.
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