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arXiv · 2204.10077

Le rang des tissus de Nakai

Jean Paul Dufour·Daniel Lehmann
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Abstract

According to Alain H\'enaut, a planar 4-web is called Nakai's web if the cross-ratio of the tangents to the four foliations at each point is constant and if it has no hexagonal 3-subweb. We prove that Nakai's webs have rank 0 or 1. We give examples with rank 1 and present a universal way to build such examples.

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Jean Paul Dufour, Daniel Lehmann. 2022-04-21. Le rang des tissus de Nakai. https://arxiv.org/abs/2204.10077

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