On October 4, 2022, Zixiang Xu (徐子翔) from the IBS Extremal Combinatorics and Probability Group gave a talk at the Discrete Math Seminar on the Turán numbers of bipartite graphs and recent approaches. The title of his talk was “On the degenerate Turán problems“.

## Santiago Guzmán-Pro gave an online talk on characterizing hereditary graph classes definable by forbidden orientations at the Virtual Discrete Math Colloquium

On September 29, 2022, Santiago Guzmán-Pro from the Universidad Nacional Autónoma de México (UNAM), Mexico gave an online talk on characterizing hereditary graph classes definable by forbidden orientations at the Virtual Discrete Math Colloquium. The title of his talk was “Local expressions of graphs classes“.

## Alexander Clifton gave a talk on the existence of a monochromatic increasing sequence with all gaps in a fixed set in any coloring of the set of positive integers at the Discrete Math Seminar

On September 27, 2022, Alexander Clifton from the IBS Discrete Mathematics Group gave a talk on the existence of a monochromatic increasing sequence with all gaps in a fixed set in any coloring of the set of positive integers at the Discrete Math Seminar. The title of his talk was “Ramsey Theory for Diffsequences“.

## Sebastian Wiederrecht gave a talk on the minor obstruction to admitting a tree decomposition into graphs each having bounded genus after removing a bounded number of apex vertices at the Discrete Math Seminar

On September 13, 2022, Sebastian Wiederrecht from the IBS Discrete Mathematics Group gave a talk at the Discrete Math Seminar on the minor obstruction to admitting a tree decomposition into graphs each having bounded genus after removing a bounded number of apex vertices and its application to the characterization of minor-closed graph classes admitting efficient algorithms to count perfect matchings. The title of his talk was “Killing a vortex“.

## Bjarne Schülke gave a talk on the proof of Frankl’s conjecture on a local version of Katona’s intersection theorem for large instances at the Discrete Math Seminar

On September 6, 2022, Bjarne Schülke from Caltech gave a talk at the Discrete Math Seminar on the proof of Frankl’s conjecture on a local version of Katona’s intersection theorem at the Discrete Math Seminar. The title of his talk was “A local version of Katona’s intersection theorem“.

## Raphael Steiner gave an online talk on finding a subdivision of a fixed directed graph with conditions on the length of a path replacing each edge in a digraph of large dichromatic number at the Virtual Discrete Math Colloquium

On August 31, 2022, Raphael Steiner from the ETH Zürich gave an online at the Virtual Discrete Math Colloquium on the existence of a subdivision of a fixed digraph satisfying constraints on the length of a path replacing each edge in a directed graph of large dichromatic number. The title of his talk was “Congruence-constrained subdivisions in digraphs“.

## Jun Gao gave a talk about the tight upper bound on the number of (k-1)-cliques in a k-critical graph at the Discrete Math Seminar

On August 30, 2022, Jun Gao (高峻) from the IBS Extremal Combinatorics and Probability Group gave a talk at the Discrete Math Seminar about the tight upper bound on the number of (k-1)-cliques in a k-critical graph, solving the conjecture of Abbott and Zhou in 1992. The title of his talk was “Number of (k-1)-cliques in k-critical graph“.

## Raul Lopes gave a talk on analogs of Menger’s theorem on temporal graphs at the Discrete Math Seminar

On August 23, 2022, Raul Lopes from LAMSADE, CNRS of Paris, France gave a talk at the Discrete Math Seminar about analogs of Menger’s theorem on temporal graphs. The title of his talk was “Temporal Menger and related problems“.

## Noleen Köhler gave a talk on the comparision of testable properties on graphs of bounded maximum degree and properties expressible by the first-order logic at the Discrete Math Seminar

On August 16, 2022, Noleen Köhler from the CNRS, LAMSADE gave a talk at the Discrete Math Seminar on comparing testable properties on graphs of bounded maximum degree and properties expressible by the first-order logic. The title of her talk was “Testing first-order definable properties on bounded degree graphs“. She is currently visiting the IBS Discrete Mathematics Group from August 6 to August 26.

## Eun Jung Kim gave a talk on a randomized algorithm for a flow-augmentation in digraphs and its applications on the paramerized complexity at the Discrete Math Seminar

On August 9, 2022, Eun Jung Kim (김은정) from CNRS, LAMSADE, Paris gave a talk at the Discrete Math Seminar on a randomized algorithm for a flow-augmentation in digraphs and its applications for parameterized complexity. The title of her talk was “Directed flow-augmentation”.