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Related papers: On the Frankl's union-closed conjecture

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We let $\mathcal{F}$ be a finite family of sets closed under taking unions and $\emptyset \not \in \mathcal{F}$, and call an element abundant if it belongs to more than half of the sets of $\mathcal{F}$. In this notation, the classical…

Combinatorics · Mathematics 2023-05-31 Adam Kabela , Michal Polák , Jakub Teska

The Union-Closed Sets Conjecture, also known as Frankl's conjecture, asks whether, for any union-closed set family $\mathcal{F}$ with $m$ sets, there is an element that lies in at least $\frac{1}{2}\cdot m$ sets in $\mathcal{F}$. In 2022,…

Combinatorics · Mathematics 2024-12-10 Saintan Wu

In 1979 Frankl conjectured that in a finite non-trivial union-closed collection of sets there has to be an element that belongs to at least half the sets. We show that this is equivalent to the conjecture that in a finite non-trivial graph…

Combinatorics · Mathematics 2013-05-17 Henning Bruhn , Pierre Charbit , Oliver Schaudt , Jan Arne Telle

In this paper, we introduce the notion of the universe, induced communities, and cells with their corresponding spots. Using this language, we formulate and prove the union close set conjecture by showing that for any finite universe…

General Mathematics · Mathematics 2026-03-10 Theophilus Agama

It is well known that in Zermelo-Fraenkel (ZF) set theory any finite set is decidable. In this paper we discuss an extension of ZF where this result is no longer valid. Such an extension is quasi-set theory and it has its origin on problems…

Quantum Physics · Physics 2007-05-23 Adonai S. Sant'Anna

The Union-Closed Sets Conjecture, often attributed to P\'eter Frankl in 1979, remains an open problem in discrete mathematics. It posits that for any finite family of sets $S\neq\{\emptyset\}$, if the union of any two sets in the family is…

Combinatorics · Mathematics 2024-05-31 Kengbo Lu , Abigail Raz

Gilmer has recently shown that in any nonempty union-closed family $\mathcal F$ of subsets of a finite set, there exists an element contained in at least a proportion $.01$ of the sets of $\mathcal F$. We improve the proportion from $.01$…

Combinatorics · Mathematics 2023-06-21 Will Sawin

The Frankl conjecture, also known as the union-closed sets conjecture, states that in any finite non-empty union-closed family, there exists an element in at least half of the sets. Let $f(n,a)$ be the maximum number of sets in a…

Combinatorics · Mathematics 2020-04-14 Brianna Amaral , Lucien Dalton , Drew Polakowski , Annie Raymond , Bertram Thomas

A family of sets is union-closed (UC) if the union of any two sets in the family is also in the family. Frankl's UC sets conjecture states that for any nonempty UC family $\mathcal{F} \subseteq 2^{[n]}$ such that $\mathcal{F} \neq…

Combinatorics · Mathematics 2019-03-07 Jonad Pulaj

The Union Closed Sets Conjecture is one of the most renowned problems in combinatorics. Its appeal lies in the simplicity of its statement contrasted with the potential complexity of its resolution. The conjecture posits that, in any union…

Combinatorics · Mathematics 2025-10-02 Nived J M

We prove Union-Closed sets conjecture.

Combinatorics · Mathematics 2024-09-13 Vladimir Blinovsky , Llohann D Speranca

The union-closed sets conjecture states that if a family of sets $\mathcal{A} \neq \{\emptyset\}$ is union-closed, then there is an element which belongs to at least half the sets in $\mathcal{A}$. In 2001, D. Reimer showed that the average…

Combinatorics · Mathematics 2017-04-25 Abigail Raz

We find previously unknown families of sets which ensure Frankl's conjecture holds for all families that contain them using an algorithmic framework. The conjecture states that for any nonempty union-closed (UC) family there exists an…

Combinatorics · Mathematics 2018-06-05 Jonad Pulaj

We provide a proof of the union-closed sets conjecture, by means of a suitable refinement of the breakthrough entropy-approach introduced by Gilmer. The novelty here is to consider a convex combination of $A$ and $A\cup B$, where $A,B$ are…

Combinatorics · Mathematics 2023-02-09 Raffaele Scandone

We verify an explicit inequality conjectured recently by Gilmer, thus proving that for any nonempty union-closed family $F \subseteq 2^{[n]}$, some $i\in [n]$ is contained in at least a $\frac{3-\sqrt{5}}{2} \approx 0.38$ fraction of the…

Combinatorics · Mathematics 2024-07-09 Ryan Alweiss , Brice Huang , Mark Sellke

We provide a simple proof for the union-closed sets conjecture, a long-standing open problem in set theory with immediate applications to graph theory, number theory, and order-theory.

Combinatorics · Mathematics 2016-07-08 Sven Schäge

Frankl's conjecture, also known as the union-closed sets conjecture, can be equivalently expressed in terms of intersection-closed set families by considering the complements of sets. It posits that any family of sets closed under…

Combinatorics · Mathematics 2025-04-21 Masahiro Hachimori , Kenji Kashiwabara

Let $F(G)$ and $b(G)$ respectively denote the Fitting subgroup and the largest degree of an irreducible complex character of a finite group $G$. A well-known conjecture of D. Gluck claims that if $G$ is solvable then $|G:F(G)|\leq…

Group Theory · Mathematics 2014-09-24 James P. Cossey , Zoltán Halasi , Attila Maróti , Hung Ngoc Nguyen

In a classical paper by Ben-David and Magidor, a model of set theory was exhibited in which $\aleph_{\omega+1}$ carries a uniform ultrafilter that is $\theta$-indecomposable for every uncountable cardinal $\theta<\aleph_\omega$. In this…

Logic · Mathematics 2025-12-18 Sittinon Jirattikansakul , Inbar Oren , Assaf Rinot

For a finite set of non-zero natural numbers that contains at least one element different from 1 and the least common multiple of any of its subsets, there exists a subset of at least half of its members which has a common divisor larger…

Number Theory · Mathematics 2018-08-29 Tom Fischer