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arXiv · 2310.18939

More on $r$-cross $t$-intersecting families for vector spaces

Tian Yao·Dehai Liu·Kaishun Wang
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Abstract

Let $V$ be a finite dimensional vector space over a finite field. Suppose that $\mathscr{F}_1$, $\mathscr{F}_2$, $\dots$, $\mathscr{F}_r$ are $r$-cross $t$-intersecting families of $k$-subspaces of $V$. In this paper, we determine the extremal structure when $\prod_{i=1}^r|\mathscr{F}_i|$ is maximum under the condition that $\dim(\bigcap_{F\in\mathscr{F}_i}F)<t$ for each $i$.

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Tian Yao, Dehai Liu, Kaishun Wang. 2024-04-30. More on $r$-cross $t$-intersecting families for vector spaces. https://arxiv.org/abs/2310.18939

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