On April 27, 2022, Michael Savery from the Oxford University gave an online talk at the Virtual Discrete Math Colloquium on finding a graph of huge chromatic number such that every induced subgraph of large chromatic number has an induced copy of a fixed subgraph at the Virtual Discrete Math Colloquium. The title of his talk was “Induced subgraphs of induced subgraphs of large chromatic number“.

## Boram Park (박보람) gave a talk on the odd coloring of graphs at the Discrete Math Seminar

On April 25, 2022, Boram Park (박보람) from Ajou University gave a talk at the Discrete Math Seminar on the odd coloring of graphs, which is a proper coloring of a graph such that every non-isolated vertex has a color having an odd number of neighbors having that color. The title of her talk was “Odd coloring of sparse graphs“.

## Jakub Gajarský gave an online talk on the FO model checking on Interpretations of Classes of Bounded Local Clique-width at the Virtual Discrete Math Colloquium

On April 13, 2022, Jakub Gajarský from the University of Warsaw gave an online talk at the Virtual Discrete Math Colloquium on the FO model checking on interpretations of classes of graphs of bounded local clique-width. The title of his talk was “Model Checking on Interpretations of Classes of Bounded Local Clique-Width“.

## Younjin Kim (김연진) gave a talk on the number of k-dimensional corner-free subsets in the k-dimensional grid at the Discrete Math Seminar

On April 11, 2022, Younjin Kim (김연진) from POSTECH gave a talk at the Discrete Math Seminar on the number of k-dimensional corner-free subsets of the k-dimensional grid {1,2,…n}^k. The title of her talk was “On the extremal problems related to Szemerédi’s theorem”.

## The ECOPRO Opening Conference was held online from April 4 to April 6

To celebrate the opening of the IBS Extremal Combinatorics and Probability Group, the IBS ECOPRO Opening Conference was held online from April 4 to April 6. There were 10 invited speakers and more than 100 participants.

### Day 1: April 4 Monday

**Jeong Han Kim**, 7:15-8:00pm**Majority dynamics on sparse random graphs**

**Oleg Pikhurko**, 8:00-8:45pm*Moser-Tardos Algorithm with small number of random bits*

**Jeff Kahn**, 8:45-9:30pm*Linear cover time is exponentially unlikely*

**Noga Alon**, 9:30-10:15pm*Random processes of graphs and permutations*

### Day 2: April 5 Tuesday

**Mihyun Kang**, 8:00-8:45pm*Random subgraphs of the hypercube*

**József Balogh, **8:45-9:30pm*On Robustness of The Erdős-Ko-Rado Theorem*

**Benny Sudakov**, 9:30-10:15pm*Short proofs of rainbow matching results*

### Day 3: April 6 Wednesday

**Van Vu**, 8:00-8:45pm/1:00-1:45pm/7:00-7:45am*Majority dynamics on a random graph: The power of few*

**Tibor Szabó**, 8:45-9:30pm*Topology at the North Pole*

**Nati Linial, **9:30-10:15pm*Geodesic Geometry of Graphs*

## Hong Liu is appointed as the CI of the new group, “IBS Extremal Combinatorics and Probability Group (ECOPRO)” as of April 1

On April 1, 2022, Hong Liu from the University of Warwick is appointed as the Chief Investigator to lead a new group, the IBS Extremal Combinatorics and Probability Group (ECOPRO), in the Center for Mathematical and Computational Sciences. To enhance our collaboration, the IBS Discrete Mathematics Group will move to the 3rd floor of the theory building on April 19-21 to share the space with the Extremal Combinatorics and Probability Group.