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arXiv · 2101.08644

Statistics for $S_n$ acting on $k$-sets

Nick Gill·Bianca Lodá
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Abstract

We study the natural action of $S_n$ on the set of $k$-subsets of the set $\{1,\dots, n\}$ when $1\leq k \leq \frac{n}{2}$. For this action we calculate the maximum size of a minimal base, the height and the maximum length of an irredundant base. Here a "base" is a set with trivial pointwise stabilizer, "height" is the maximum size of a subset with the property that its pointwise stabilizer is not equal to the pointwise stabilizer of any proper subset, and an "irredundant base" can be thought of as a chain of (pointwise) set-stabilizers for which all containments are proper.

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Nick Gill, Bianca Lodá. 2021-01-21. Statistics for $S_n$ acting on $k$-sets. https://arxiv.org/abs/2101.08644

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