Charles University

output

19922026

most citedObservation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC

10.9k citations

researchers with a paper here

Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.

collaborating institutions

Showing 2021 · math.COShow all

11 papers · 2 filters

math.CO2021★ 2 cited

Recolouring planar graphs of girth at least five

Valentin Bartier, Nicolas Bousquet, Carl Feghali +3

For a positive integer $k$ , the $k$ -recolouring graph of a graph $G$ has as vertex set all proper $k$ -colourings of $G$ with two $k$ -colourings being adjacent if they differ by the…

math.CO2021

Avoiding a pair of patterns in multisets and compositions

Vít Jelínek, Toufik Mansour, José L. Ramírez +1

In this paper, we study the Wilf-type equivalence relations among multiset permutations. We identify all multiset equivalences among pairs of patterns consisting of a pattern of le…

math.CO2021

Minimal asymmetric hypergraphs

Yiting Jiang, Jaroslav Nesetril

In this paper, we prove that for any $k \geq 3$ , there exist infinitely many minimal asymmetric $k$ -uniform hypergraphs. This is in a striking contrast to $k = 2$ , where it has been pr…

math.CO2021★ 4 cited

Weak saturation of multipartite hypergraphs

Denys Bulavka, Martin Tancer, Mykhaylo Tyomkyn

Given $q$ -uniform hypergraphs ( $q$ -graphs) $F, G$ and $H$ , where $G$ is a spanning subgraph of $F$ , $G$ is called weakly $H$ -saturated in $F$ if the edges in $E (F) ∖ E (G)$ ad…

math.CO2021★ 3 cited

Universality in minor-closed graph classes

Tony Huynh, Bojan Mohar, Robert Šámal +2

Stanislaw Ulam asked whether there exists a universal countable planar graph (that is, a countable planar graph that contains every countable planar graph as a subgraph). János Pac…

math.CO2021

Ramsey expansions of 3-hypertournaments

Gregory Cherlin, Jan Hubička, Matěj Konečný +1

We study Ramsey expansions of certain homogeneous 3-hypertournaments. We show that they exhibit an interesting behaviour and, in one case, they seem not to submit to current gold-s…

math.CO2021

Bears with Hats and Independence Polynomials

Václav Blažej, Pavel Dvořák, Michal Opler

Consider the following hat guessing game. A bear sits on each vertex of a graph $G$ , and a demon puts on each bear a hat colored by one of $h$ colors. Each bear sees only the hat c…

math.CO2021★ 8 cited

Random 2-cell embeddings of multistars

Jesse Campion Loth, Kevin Halasz, Tomáš Masařík +2

Random 2-cell embeddings of a given graph $G$ are obtained by choosing a random local rotation around every vertex. We analyze the expected number of faces, $E [F_{G}]$ , of s…

math.CO2021★ 4 cited

The Phase Transition of Discrepancy in Random Hypergraphs

Calum MacRury, Tomáš Masařík, Leilani Pai +1

Motivated by the Beck-Fiala conjecture, we study the discrepancy problem in two related models of random hypergraphs on $n$ vertices and $m$ edges. In the first (edge-independent)…

math.CO2021★ 1 cited

Division sudokus: Invariants, enumeration and multiple partitions

Aleš Drápal, Petr Vojtěchovský

A division sudoku is a latin square whose all six conjugates are sudoku squares. We enumerate division sudokus up to a suitable equivalence, introduce powerful invariants of divisi…

math.CO2021★ 1 cited

On Aharoni's rainbow generalization of the Caccetta-Häggkvist conjecture

Patrick Hompe, Petra Pelikanova, Aneta Pokorna +1

For a digraph $G$ and $v \in V (G)$ , let $δ^{+} (v)$ be the number of out-neighbors of $v$ in $G$ . The Caccetta-Häggkvist conjecture states that for all $k \geq 1$ , if $G$ is a digraph…