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arXiv · 2509.14790

The Story of Sunflowers

Anup Rao
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Abstract

Sunflowers, or $Δ$-systems, are a fundamental concept in combinatorics introduced by Erdős and Rado in their paper: {\em Intersection theorems for systems of sets}, J. Lond. Math. Soc. (1) {\bf 35} (1960), 85--90. A sunflower is a collection of sets where all pairs have the same intersection. This paper explores the wide-ranging applications of sunflowers in computer science and combinatorics. We discuss recent progress towards the sunflower conjecture and present a short elementary proof of the best known bounds for the robust sunflower lemma.

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Anup Rao. 2025-09-18. The Story of Sunflowers. https://arxiv.org/abs/2509.14790

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