Publications de Andrei Kupavskii

On the Size of K-Cross-Free Families

János Pach, Andrei Kupavskii, Istvan Tomon

Two subsets A,B of an n-element ground set X are said to be crossing, if none of the four sets AB, A\B, B\A and X(AB) are empty. It was conjectured by Karzanov and Lomonosov forty years ago that if a family F of subsets of X does not contain k pairwise cr ...

SPRINGER HEIDELBERG2019

Counting Intersecting and Pairs of Cross-Intersecting Families

Andrei Kupavskii

A family of subsets of {1, ... , n} is called intersecting if any two of its sets intersect. A classical result in extremal combinatorics due to Erdos, Ko and Rado determines the maximum size of an intersecting family of k-subsets of {1, ... , n}. In this ...

Cambridge Univ Press2018

Colourings of Uniform Hypergraphs with Large Girth and Applications

Andrei Kupavskii

2018

CONTROLLING LIPSCHITZ FUNCTIONS

János Pach, Gábor Tardos, Andrei Kupavskii

2018

FAMILIES OF VECTORS WITHOUT ANTIPODAL PAIRS

Andrei Kupavskii

2018

Regular bipartite graphs and intersecting families

Andrei Kupavskii

2018

Tilings of the plane with unit area triangles of bounded diameter

János Pach, Gábor Tardos, Andrei Kupavskii

2018

On Simplices in Diameter Graphs in R-4

Andrei Kupavskii

A graph G is a diameter graph in R-d if its vertex set is a finite subset in R-d of diameter 1 and edges join pairs of vertices a unit distance apart. It is shown that if a diameter graph G in R-4 contains the complete subgraph K on five vertices, then any ...

Maik Nauka/Interperiodica/Springer2017

Uniform s-Cross-Intersecting Families

Andrei Kupavskii

In this paper we study a question related to the classical Erdos-Ko-Rado theorem, which states that any family of k-element subsets of the set [n] = {1,..., n} in which any two sets intersect has cardinality at most ((n-1)(k-1)). We say that two non-empty ...

Cambridge Univ Press2017

Families with no s pairwise disjoint sets

Andrei Kupavskii

For integers n >= s >= 2 let e (n, s) denote the maximum of vertical bar F vertical bar, where F is a family of subsets of an n- element set and F contains no s pairwise disjoint members. Half a century ago, solving a conjecture of Erd. os, Kleitman determ ...

Wiley2017