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arXiv 2108.07692math.CO
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Erdens-Ko-Rado定理在均匀集划分上的推广

An Extension of the Erdős-Ko-Rado Theorem to uniform set partitions

Karen Meagher, Mahsa N. Shirazi, Brett Stevens

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19 pages
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摘要：

$(k,\ell)$分区是具有每个大小为$k$的$\ell$块的集合分区。如果在$P$中存在块$P_{i}$并且在$Q$中存在块$Q_{j}$使得$\left| P_{i} \cap Q_{j} \right|\geq t$，则两个均匀集划分$P$和$Q$被称为部分$t$相交。本文证明了部分$2$ -相交$(k,\ell)$ -划分的Erdens-Ko-Rado定理的一个版本。特别是，我们表明$\ell$足够大，所有的$(k,\ell)$分区，其中一个块包含一个固定的对的集合是最大的2部分相交的$(k,\ell)$分区。对于$k=3$，我们证明了这个结果对所有$\ell$都成立。

英文摘要：

A $(k,\ell)$-partition is a set partition which has $\ell$ blocks each of size $k$. Two uniform set partitions $P$ and $Q$ are said to be partially $t$-intersecting if there exist blocks $P_{i}$ in $P$ and $Q_{j}$ in $Q$ such that $\left| P_{i} \cap Q_{j} \right|\geq t$. In this paper we prove a version of the Erdős-Ko-Rado theorem for partially $2$-intersecting $(k,\ell)$-partitions. In particular, we show for $\ell$ sufficiently large, the set of all $(k,\ell)$-partitions in which a block contains a fixed pair is the largest set of 2-partially intersecting $(k,\ell)$-partitions. For for $k=3$, we show this result holds for all $\ell$.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

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