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arXiv · 1705.00176

On an extremal problem for poset dimension

Grzegorz Guśpiel·Piotr Micek·Adam Polak
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Abstract

Let $f(n)$ be the largest integer such that every poset on $n$ elements has a $2$-dimensional subposet on $f(n)$ elements. What is the asymptotics of $f(n)$? It is easy to see that $f(n)\geqslant n^{1/2}$. We improve the best known upper bound and show $f(n)=\mathcal{O}(n^{2/3})$. For higher dimensions, we show $f_d(n)=\mathcal{O}\left(n^\frac{d}{d+1}\right)$, where $f_d(n)$ is the largest integer such that every poset on $n$ elements has a $d$-dimensional subposet on $f_d(n)$ elements.

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Grzegorz Guśpiel, Piotr Micek, Adam Polak. 2017-11-03. On an extremal problem for poset dimension. https://doi.org/10.1007/s11083-017-9444-1

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