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arXiv · 2602.11796

Frankl's diversity theorem for permutations

Eduard Inozemtsev·Andrey Kupavskii
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Abstract

In 1987, Frankl proved an influential stability result for the Erd\H os--Ko--Rado theorem, which bounds the size of an intersecting family in terms of its distance from the nearest (subset of) star or trivial intersecting family. It is a far-reaching extension of the Hilton--Milner theorem. In this paper, we prove its analogue for permutations on $\{1,\ldots, n\}$, provided $n$ is large. This provides a similar extension of a Hilton--Milner type result for permutations proved by Ellis.

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Eduard Inozemtsev, Andrey Kupavskii. 2026-02-12. Frankl's diversity theorem for permutations. https://arxiv.org/abs/2602.11796

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