On August 4, 2020, June Huh (허준이) from Institute of Advanced Study presented several conjectures on Kazhdan-Lusztig polynomials of graphs and matroids and recent progress towards them at the Discrete Math Seminar. The title of his talk was “Kazhdan-Lusztig polynomials of graphs and matroids“.
Akanksha Agrawal gave a talk on the polynomial kernel for interval vertex deletion at the Virtual Discrete Math Colloquium
On July 29, 2020, Akanksha Agrawal from Ben-Gurion University of the Negev gave the second talk of the online seminar series called the Virtual Discrete Math Colloquium. The title of her talk was “Polynomial Kernel for Interval Vertex Deletion“.
Eun Jung Kim (김은정) gave a talk on a new technique called the flow augmentation to design fixed-parameter algorithms for graph cut problems at the Discrete Math Seminar
On July 28, 2020, Eun Jung Kim (김은정) from CNRS, LAMSADE gave a talk on a new tool called the flow augmentation, that is useful to design fixed-parameter algorithms for various graph cut problems on undirected graphs. The title of her talk was “Solving hard cut problems via flow-augmentation“.
We started the Virtual Discrete Math Colloquium from July 22; the first speaker was Paloma T. Lima.
Due to the COVID-19 pandemic, we decided to start a new series of talks given online under the name “Virtual Discrete Math Colloquium” so that we can invite speakers abroad online. On July 22, 2020, its first talk was given by Paloma T. Lima from University of Bergen, Norway. She talked about the problem of deciding whether a given input graph G is a square of some graph H with some restrictions on H. The title of her talk was “Graph Square Roots of Small Distance from Degree One Graphs“.
Ilkyoo Choi (최일규) gave a talk on the flexibility of planar graphs related to a problem of extending a precoloring at the Discrete Math Seminar
On July 21, 2020, Ilkyoo Choi (최일규) from Hankuk University of Foreign Studies gave a talk on the flexibility of planar graphs, a concept related to extending a a precoloring at the Discrete Math Seminar. The title of his talk was “Flexibility of Planar Graphs“.
Casey Tompkins gave a talk on inverse Turán problems at the Discrete Math Seminar
On July 14, 2020, Casey Tompkins from IBS Discrete Mathematics Group gave a talk on inverse Turán problems at the Discrete Math Seminar. The goal is for a fixed graph H and an integer k to find the minimum number of edges of a graph G such that that every subgraph of G with at least k edges has a subgraph isomorphic to H. The title of his talk is “Inverse Turán Problems“.
Seog-jin Kim (김석진) gave a talk on the Online DP-coloring of graphs at the Discrete Math Seminar
On July 7, 2020, Seog-jin Kim (김석진) from Konkuk University presented his work on the online DP-coloring of graphs, a common generalization of the online coloring and the DP coloring, both generalizing the list coloring of graphs. The title of his talk was “Online DP-coloring of graphs“. He will stay at the IBS discrete mathematics group until the end of this week.
Dennis Wong presented a talk on algorithms to generate Gray codes and universal cycles for weak orders at the Discrete Math Seminar
On June 30, 2020, Dennis Wong from SUNY Korea gave a talk on algorithms to generate Gray codes and universal cycles for weak orders at the Discrete Math Seminar. At the end of the talk, his student, Fabio Calero from SUNY Korea, gave a sketch about another work on Gray codes for ballot sequences. The title of his talk is “Generating Gray codes and universal cycles for weak orders“.

Jaehoon Kim (김재훈) gave a talk on a resilience version of Pósa’s theorem regarding Hamiltonian cycles at the Discrete Math Seminar
On June 23, 2020, Jaehoon Kim (김재훈) from KAIST presented his work with Padraig Condon, Alberto Espuny Diaz, Daniela Kühn and Deryk Osthus on a resilience version of Pósa’s theorem regarding a sufficient condition on the degree sequence for a graph to have a Hamiltonian cycle at the Discrete Math Seminar. The title of his talk is “A resilience version of Pósa’s theorem“.
Andreas Holmsen gave a talk on a recent work generalizing the fractional Helly theorem under very weak topological assumptions at the Discrete Math Seminar
On June 16, 2020, Andreas Holmsen from KAIST presented his recent work with Xavier Goaoc and Zuzana Patáková on generalizing the fractional Halley theorem under very weak topological assumptions. The title of his talk was “Fractional Helly and topological complexity“.