English
Related papers

Related papers: On the "second" Kahn--Kalai Conjecture

200 papers

The work deals with the threshold probablity for r-colorability in the binomial model H(n,k,p) of a random k-uniform hypergraph. We prove a lower bound for this threshold which improves the previously known results in the wide range of the…

Combinatorics · Mathematics 2017-12-01 Andrei Kupavskii , Dmitry Shabanov

We prove that every $3$-graph $H$ on $n$ vertices with minimum codegree $\delta_2(H) \geq 7n/9 + o(n)$ contains the square of a tight Hamilton cycle. This strengthens a theorem of Bedenknecht and Reiher that $\delta_2(H) \geq 4n/5 + o(n)$…

Combinatorics · Mathematics 2026-03-31 Debmalya Bandyopadhyay , Allan Lo , Richard Mycroft

We establish a relation between two uniform models of random $k$-graphs (for constant $k \ge 3$) on $n$ labeled vertices: $H(n,m)$, the random $k$-graph with exactly $m$ edges, and $H(n,d)$, the random $d$-regular $k$-graph. By extending to…

Combinatorics · Mathematics 2019-02-20 Andrzej Dudek , Alan Frieze , Andrzej Ruciński , Matas Šileikis

The generalized $k$-connectivity $\kappa_{k}(G)$ of a graph $G$, which was introduced by Chartrand et al.(1984) is a generalization of the concept of vertex connectivity. Let $G$ and $H$ be nontrivial connected graphs. Recently, Li et al.…

Combinatorics · Mathematics 2017-05-24 Hui Gao , Benjian Lv , Kaishun Wang

Borrowing L\'aszl\'o Sz\'ekely's lively expression, we show that Hill's conjecture is "asymptotically at least 98.5% true". This long-standing conjecture states that the crossing number cr($K_n$) of the complete graph $K_n$ is $H(n) :=…

Combinatorics · Mathematics 2020-06-12 József Balogh , Bernard Lidický , Gelasio Salazar

The Planar Graph Metric Compression Problem is to compactly encode the distances among $k$ nodes in a planar graph of size $n$. Two na\"ive solutions are to store the graph using $O(n)$ bits, or to explicitly store the distance matrix with…

Data Structures and Algorithms · Computer Science 2017-03-16 Amir Abboud , Pawel Gawrychowski , Shay Mozes , Oren Weimann

One of the most elusive challenges within the area of topological data analysis is understanding the distribution of persistence diagrams. Despite much effort, this is still largely an open problem. In this paper, we present a series of…

Statistics Theory · Mathematics 2022-07-11 Omer Bobrowski , Primoz Skraba

We propose the following conjecture extending Dirac's theorem: if $G$ is a graph with $n\ge 3$ vertices and minimum degree $\delta(G)\ge n/2$, then in every orientation of $G$ there is a Hamilton cycle with at least $\delta(G)$ edges…

Combinatorics · Mathematics 2023-03-13 Lior Gishboliner , Michael Krivelevich , Peleg Michaeli

A conjecture of Khang Tran [6] claims that for an arbitrary pair of polynomials $A(z)$ and $B(z)$, every zero of every polynomial in the sequence $\{P_n(z)\}_{n=1}^\infty$ satisfying the three-term recurrence relation of length $k$…

Classical Analysis and ODEs · Mathematics 2020-03-18 Rikard Bögvad , Innocent Ndikubwayo , Boris Shapiro

Hill's Conjecture states that the crossing number $\text{cr}(K_n)$ of the complete graph $K_n$ in the plane (equivalently, the sphere) is…

Combinatorics · Mathematics 2021-03-22 Alan Arroyo , Dan McQuillan , R. Bruce Richter , Gelasio Salazar , Matthew Sullivan

Recently, a short proof of the Harris-Kesten result that the critical probability for bond percolation in the planar square lattice is 1/2 was given, using a sharp threshold result of Friedgut and Kalai. Here we point out that a key part of…

Probability · Mathematics 2009-05-08 Bela Bollobas , Oliver Riordan

Dirac's classical theorem asserts that, for $n \ge 3$, any $n$-vertex graph with minimum degree at least $n/2$ is Hamiltonian. Furthermore, if we additionally assume that such graphs are regular, then, by the breakthrough work of Csaba,…

We give a simple method to estimate the number of distinct copies of some classes of spanning subgraphs in hypergraphs with high minimum degree. In particular, for each $k\geq 2$ and $1\leq \ell\leq k-1$, we show that every $k$-graph on $n$…

Combinatorics · Mathematics 2024-11-20 Richard Montgomery , Matías Pavez-Signé

Consider a uniformly random regular graph of a fixed degree $d\ge3$, with $n$ vertices. Suppose that each edge is open (closed), with probability $p(q=1-p)$, respectively. In 2004 Alon, Benjamini and Stacey proved that $p^*=(d-1)^{-1}$ is…

Probability · Mathematics 2008-08-27 Boris Pittel

P\'or and Wood conjectured that for all $k,l \ge 2$ there exists $n \ge 2$ with the following property: whenever $n$ points, no $l + 1$ of which are collinear, are chosen in the plane and each of them is assigned one of $k$ colours, then…

Combinatorics · Mathematics 2014-10-13 Vytautas Gruslys

An \emph{$(n,k,t)$-graph} is a graph on $n$ vertices in which every set of $k$ vertices contains a clique on $t$ vertices. Tur\'an's Theorem, rephrased in terms of graph complements, states that the unique minimum $(n,k,2)$-graph is an…

Combinatorics · Mathematics 2025-05-19 Stacie Baumann , Joseph Briggs

We show that $p=\sqrt{\frac{e}{n}}$ is a sharp threshold for the random graph $G_{n,p}$ to contain the square of a Hamilton cycle. This improves the previous results of K\"uhn and Osthus and also Nenadov and \v{S}kori\'c.

Combinatorics · Mathematics 2016-09-20 Andrzej Dudek , Alan Frieze

Frankl and F\"uredi conjectured in 1989 that the maximum Lagrangian of all $r$-uniform hypergraphs of fixed size $m$ is realized by the minimum hypergraph $C_{r,m}$ under the colexicographic order. In this paper, we prove a weaker version…

Combinatorics · Mathematics 2018-06-29 Hui Lei , Linyuan Lu , Yuejian Peng

The P\'osa-Seymour conjecture asserts that every graph on $n$ vertices with minimum degree at least $(1 - 1/(r+1))n$ contains the $r^{th}$ power of a Hamilton cycle. Koml\'os, S\'ark\"ozy and Szemer\'edi famously proved the conjecture for…

Combinatorics · Mathematics 2022-08-29 Domagoj Bradač

We locate the critical threshold $p_c$ at which it becomes likely that the complete graph $K_n$ can be obtained from the Erd\H{o}s-R\'enyi graph ${\cal G}_{n,p}$ by iteratively completing copies of $K_4$ minus an edge. This refines work of…

Probability · Mathematics 2025-11-18 Brett Kolesnik