Helly-type problems

Bárány, Imre; Kalai, Gil

doi:10.1090/bull/1753

Helly-type problems
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by Imre Bárány and Gil Kalai;

Bull. Amer. Math. Soc. 59 (2022), 471-502

DOI: https://doi.org/10.1090/bull/1753

Published electronically: October 29, 2021

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Abstract:

In this paper we present a variety of problems in the interface between combinatorics and geometry around the theorems of Helly, Radon, Carathéodory, and Tverberg. Through these problems we describe the fascinating area of Helly-type theorems and explain some of their main themes and goals.

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