5 papers · 1 filter
A note on universal graphs for spanning trees
Ervin Győri, Binlong Li, Nika Salia +1
Chung and Graham considered the problem of minimizing the number of edges in an -vertex graph containing all -vertex trees as a subgraph. They showed that such a graph has at…
The maximum Wiener index of a uniform hypergraph
Stijn Cambie, Ervin Győri, Nika Salia +2
The Wiener index of a (hyper)graph is calculated by summing up the distances between all pairs of vertices. We determine the maximum possible Wiener index of a connected -vertex…
On the rainbow planar Turán number of paths
Ervin Győri, Ryan R. Martin, Addisu Paulos +2
An edge-colored graph is said to contain a rainbow- if it contains as a subgraph and every edge of is a distinct color. The problem of maximizing edges among -vertex…
Exact results for generalized extremal problems forbidding an even cycle
Ervin Győri, Zhen He, Zequn Lv +4
We determine the maximum number of copies of in a -free -vertex graph for all integers and sufficiently large . Moreover, for and…
De Bruijn-Erdős type theorems for graphs and posets
Pierre Aboulker, Guillaume Lagarde, David Malec +2
A classical theorem of De Bruijn and Erdős asserts that any noncollinear set of n points in the plane determines at least n distinct lines. We prove that an analogue of this theore…