기초과학연구원 이산수학그룹
On November 11, 2025, Simón Piga from the University of Hamburg gave a talk at the Discrete Math Seminar on variants of the Turán problem for k-uniform hypergraphs. The title of his talk was “Turán problem in hypergraphs with quasirandom links“.
On November 4, 2025, Tim Hartmann and Ahemed Ghazy from CISPA Helmholtz Center for Information Security in Germany gave a talk at the Discrete Math Seminar on continuous graphs—a model obtained by replacing each edge of a graph with a unit interval to form a metric space, enabling continuous analogues of classical graph problems. The title of their talk was “Continuous Graphs – An Overview and a Coloring Problem“.
On October 28, 2025, Jakob Greilhuber from the CISPA Helmholtz Center for Information Security gave a talk at the Discrete Math Seminar on the parameterized complexity of the problem of deleting k vertices to make every component small. The title of his talk was “A Dividing Line for Structural Kernelization of Component Order Connectivity via Distance to Bounded Pathwidth“.
On October 21, 2025, William Cook from University of Waterloo gave a talk at the Discrete Math Seminar on using branch-decompositions for discrete optimization problems, including the traveling salesman problem. The title of his talk was “Optimization via Branch Decomposition“.
On October 14, 2025, Ilkyoo Choi (최일규) from Hankuk University of Foreign Studies and IBS Discrete Mathematics Group gave a talk at the Discrete Math Seminar on the average degree of list-color-critical graphs and DP-color-critical graphs. The title of his talk was “An improved lower bound on the number of edges in list critical graphs via DP coloring“.
On September 30, 2025, Marcelo Sales from the University of California, Irvine, gave a talk at the Discrete Math Seminar about proving lower bounds on the Ramsey numbers of some hypergraphs. His talk was titled “On the Ramsey number of Daisies and other hypergraphs.”
On September 22, 2025, Rong Luo from West Virginia University gave a talk at the Discrete Math Seminar on nowhere-zero flows on signed graphs. His talk was titled “Modulo flows and Integer flows of signed graphs“.
On September 16, 2025, Mujin Choi (최무진) from KAIST and the IBS Discrete Mathematics Group gave a talk at the Discrete Math Seminar on unavoidable induced minors in graphs of large tree-independence number without a fixed induced star. The title of his talk was “Excluding ladder and wheel as induced minor in graphs without induced stars“.
On September 9, 2025, Katherine Perry from the Soka University of America gave a talk at the Discrete Math Seminar on the relationship between the distinguishing number and the fixing number of trees. The title of her talk was “Symmetry breaking in trees“.
On September 2, 2025, Zhifei Yan from the IBS Extremal Combinatorics and Probability Group gave a talk at the Discrete Math Seminar on covering the vertex set of a properly edge-colored graph with two vertex-disjoint rainbow cycles. The title of his talk was “A Rainbow version of Lehel’s conjecture“.