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arXiv · 2310.05775

Essential covers of the hypercube require many hyperplanes

Lisa Sauermann·Zixuan Xu
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Abstract

We prove a new lower bound for the almost 20 year old problem of determining the smallest possible size of an essential cover of the $n$-dimensional hypercube $\{\pm 1\}^n$, i.e. the smallest possible size of a collection of hyperplanes that forms a minimal cover of $\{\pm 1\}^n$ and such that furthermore every variable appears with a non-zero coefficient in at least one of the hyperplane equations. We show that such an essential cover must consist of at least $10^{-2}\cdot n^{2/3}/(\log n)^{2/3}$ hyperplanes, improving previous lower bounds of Linial-Radhakrishnan, of Yehuda-Yehudayoff and of Araujo-Balogh-Mattos.

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Lisa Sauermann, Zixuan Xu. 2023-10-09. Essential covers of the hypercube require many hyperplanes. https://doi.org/10.1017/s0963548324000257

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