Seunghun Lee (이승훈), Transversals and colorings of simplicial spheres
Room B232 IBS (기초과학연구원)Motivated from the surrounding property of a point set in
Motivated from the surrounding property of a point set in
A geometric transversal to a family of convex sets in
The Caccetta-Haggkvist conjecture, one of the best known in graph theory, is that in a digraph with
For given
Graph Minor project by Robertson and Seymour is perhaps the deepest theory in Graph Theory. It gives a deep structural characterization of graphs without any graph
In a reduction sequence of a graph, vertices are successively identified until the graph has one vertex. At each step, when identifying
Our talk will mainly focus on the relationship between substructures and eigenvalues of graphs. We will briefly survey recent developments on a conjecture of Bollobás and Nikiforov and a classical result of Nosal on triangles. In particular, we shall present counting results for previous spectral theorems on triangles and quadrilaterals. If time allows, we will …
Erdős and Pósa proved in 1965 that there is a duality between the maximum size of a packing of cycles and the minimum size of a vertex set hitting all cycles. We therefore say that cycles satisfy the Erdős-Pósa property. However, while odd cycles do not satisfy the Erdős-Pósa property, Reed proved in 1999 an analogue by …
We prove that there is a function
An independent dominating set of a graph, also known as a maximal independent set, is a set