기초과학연구원 이산수학그룹
The IBS discrete mathematics group welcomes Dr. Zhifei Yan, a new research fellow at the IBS Extremal Combinatorics and Probability Group, starting September 1, 2025. He received his Ph.D. in 2025 from the Instituto Nacional de Matemática Pura e Aplicada (IMPA), Rio de Janeiro, Brazil, under the supervision of Prof. Rob Morris. He is interested in extremal and probabilistic combinatorics.
On August 29, 2025, Sang-il Oum (엄상일) from the IBS Discrete Mathematics Group gave a talk at the Discrete Math Seminar on the Erdős-Pósa property for vertex-minors and perturbations of graphs. The title of his talk was “The Erdős-Pósa property for circle graphs as vertex-minors“.
The 2025 Korean Student Combinatorics Workshop (KSCW2025, 2025 조합론 학생 워크샵) was held in The-K Hotel Gyeongju from August 20 to August 24, 2025. Sponsored by the IBS Discrete Mathematics Group, this event aims to provide a platform for Korean graduate students working on combinatorics and related areas to establish a foundation for collaborative research. This is a continuation of the same workshop held last year.
This workshop was organized by the following four graduate students.
The 2025 Combinatorics Workshop (2025 조합론 학술대회) was held from August 18, 2025 to August 20, 2025 at IBS, Daejeon. Combinatorics Workshop (조합론 학술대회) is an annual conference for researchers in combinatorics and related areas in Korea, started in 2004. There were 5 invited talks and 13 contributed talks.
On August 12, 2025, Chien-Chung Huang from CNRS, DI ENS gave a talk at the Discrete Math Seminar on finding a small substructure in a matroid that allows a good approximation for the matroid intersection while having some robustness properties. His talk was titled “Robust Sparsification for Matroid Intersection with Applications.”
The 2025 Summer School “Frontiers of Combinatorics” was held at IBS from July 28, 2025 to August 8, 2025. Lior Gishboliner from the University of Toronto gave a one-week-long lecture on removal lemmas and related topics. Yuval Filmus from Technion gave a 1-week-long lecture on Boolean Algebra. This school was organized by the IBS Extremal Combinatorics and Probability Group.
On August 5, 2025, Tony Huynh from the IBS Discrete Mathematics Group gave a talk at the Discrete Math Seminar on a natural extension of the multicolored version of the Erdős-Hajnal conjecture to projective geometries. The title of his talk was “Rainbow triangles and the Erdős-Hajnal problem in projective geometries“.
The IBS Discrete Mathematics Group is pleased to welcome Dr. Tony Huynh as a new senior research fellow, starting August 1, 2025. Before joining IBS, he was an assistant professor at the Sapienza Università di Roma, in Rome, Italy. He earned his Ph.D. from the Department of Combinatorics and Optimization at the University of Waterloo in Waterloo, Canada in 2009, under the supervision of Prof. Jim Geelen. He is mainly interested in graphs, matroids, and combinatorial optimization. Welcome!
On July 29, 2025, Colin Geniet from the IBS Discrete Mathematics Group gave a talk on the merge-width of graphs and 𝜒-boundedness of graphs of bounded merge-width at the Discrete Math Seminar. The title of his talk was “merge-width“.
On July 22, 2025, Linda Cook from the University of Amsterdam gave a talk at the Discrete Math Seminar on the local certification protocol for monadic second-order property on graphs of bounded tree-width. The title of her talk was “A tight algorithmic meta-theorem for distributed certification within bounded treewidth graphs“.