Invited minisymposium on the structural graph theory at CanaDAM2023

Sang-il Oum and Sebastian Wiederrecht organized an invited minisymposium at the CanaDAM 2023 (Canadian Discrete and Algorithmic Mathematics) held in Winnipeg, Canada on June 5-8, 2023. Here is the list of speakers for the minisymposium.

  • Paul Wollan (Sapienza University of Rome): “Tree decompositions into subgraphs of bounded radius”
  • Jan Kurkofka (University of Birmingham): “Canonical decompositions of 3-connected graphs”
  • Stephan Kreutzer (Technische Universität Berlin): “Towards a structure theorem for digraph minors”
  • Sebastian Wiederrecht (IBS Discrete Mathematics Group): “Universal obstructions in graph minors”
  • Youngho Yoo (Texas A&M University): “Erdős-Pósa property in undirected group-labelled graphs”
  • Eunjung Kim (LAMSADE, Université Paris-Dauphine): “When twin-width is the right measure”
  • Chun-Hung Liu (Texas A&M University): “Minor-closed families are defectively perfect”
  • Raphael Steiner (ETH Zürich): “Digraphs of large out-degree: problems and new results”
  • J. Pascal Gollin (IBS Discrete Mathematics Group): “A structural theory for odd minors”

Nika Salia organized a special session “Extremal Combinatorics: Methods and Applications” at the 2023 KMS Spring Meeting on April 28-29

On April 28-29, 2023, Nika Salia of the IBS Extremal Combinatorics and Probability Group organized a special session called “Extremal Combinatorics: Methods and Applications” at the 2023 KMS Spring Meeting held at Daejeon Convention Center, Daejeon, Korea. Here is a list of 16 talks.

   ⋅ 28th-A-09:00 − 09:20   Domination inequalities and dominating graphs (David Conlon, Joonkyung Lee)
   ⋅ 28th-A-09:20 − 09:40   C5-critical series parallel graphs (Eun-Kyung Cho, Ilkyoo Choi, Boram Park, Mark H. Siggers)
   ⋅ 28th-A-09:50 − 10:10   On the extremal problems related to Szemeredi’s theorem (Younjin Kim)
   ⋅ 28th-A-10:10 − 10:30   Bounds on maximum directed cut (Jiangdong Ai, Stefanie Gerke, Gregory Gutin, Anders Yeo, Yacong Zhou)

   ⋅ 28th-B-10:50 − 11:10   Rainbow cycles in edge-colored graphs (Joonkyung Lee, Jaehoon Kim, Hong Liu, Tuan Tran)
   ⋅ 28th-B-11:10 − 11:30   How connectivity affects the extremal number of trees (Suyun Jiang, Hong Liu, Nika Salia)
   ⋅ 28th-B-11:40 − 12:00   Many Hamiltonian subsets in large graphs with given density (Stijn Cambie, Jun Gao, Hong Liu)
   ⋅ 28th-B-12:00 − 12:20   Maximum total distance of hypergraphs (Stijn Cambie, Ervin Győri, Nika Salia, Casey Tompkins, James Tuite)

   ⋅ 28th-C-13:30 − 13:50   Intersection patterns and incidence theorems (Thang Pham, Semin Yoo)
   ⋅ 28th-C-13:50 − 14:10   Note on the quotient set of the quadratic distance set over finite fields (Doowon Koh)
   ⋅ 28th-C-14:20 − 14:40   Convexity and chi-boundedness (Andreas Holmsen)
   ⋅ 28th-C-14:40 − 15:00   Exceptional projections in finite vector spaces (Ben Lund)

   ⋅ 29th-D-09:00 − 09:20   Rainbow bandwidth theorem (Debsoumya Chakraborti, Seonghyuk Im, Jaehoon Kim, Hong Liu)
   ⋅ 29th-D-09:20 − 09:40   Covering multigraphs with bipartite graphs (Hyunwoo Lee)
   ⋅ 29th-D-09:50 − 10:10   Rainbow oriented Hamiltonian paths and cycles in tournaments (Debsoumya Chakraborti, Jaehoon Kim, Hyunwoo Lee, Jaehyeon Seo)
   ⋅ 29th-D-10:10 − 10:30   Colorful Hamilton cycles in random graphs (Debsoumya Chakraborti, Alan Frieze, Mihir Hasabnis)

KSIAM 2022 Spring Conference was held at the IBS

On May 27-29, 2022, the KSIAM 2022 Spring Conference was held at the IBS Science Culture Center, located at the IBS. For Combinatorics, there was a special session on graph theory organized by Sang-il Oum, a special session on enumerative combinatorics organized by Dongsu Kim, and an invited talk by Joonkyung Lee on May 27, 2022. Both IBS Discrete Mathematics Group and the IBS Biomedical Mathematics Group participated as one of the organizing institutions of the KSIAM 2022 Spring Conference.

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

All videos of talks at the “Round the World Relay in Combinatorics” are now available

The “Round the World Relay in Combinatorics” was held on June 8 Tuesday. Now the videos of all talks are available on YouTube.

2020 Combinatorics Workshop (2020 조합론 학술대회) was held on August 24 online

On August 24, Monday, the 2020 Combinatorics Workshop (2020 조합론 학술대회) was held online due to the COVID-19 pandemic. This local workshop series began in 2004 and has been continued to be one of the biggest annual gathering of people in combinatorics located in Korea. Due to the COVID-19 pandemic, it has been reduced to a one-day online conference on Zoom. It was hosted by Kyung Hee University and IBS Discrete Mathematics Group.

The workshop website:

There were 5 invited speakers.

  • Sejeong Bang (방세정), Yeungnam University, Geometric distance-regular graphs
  • Ringi Kim (김린기), KAIST, Decomposing planar graphs into graphs with degree restrictions
  • Sangwook Kim (김상욱), Chonnam National University, Combinatorics of lattice path matroid polytopes
  • Jinyoung Park (박진영), Institute for Advanced Study, Tuza’s Conjecture for random graphs
  • Jongyook Park (박종육), Kyungpook National University, On distance-regular graphs with induced subgraphs $K_{r,t}$

There were 4 contributed talks.

  • Byung-Hak Hwang (황병학), Seoul National University, Acyclic orientation polynomials
  • Jaeseong Oh (오재성), Seoul National University, On linearization coefficients of q-Laguerre polynomials
  • Jun Seok Oh (오준석), Incheon National University, An inverse Erdős-Ginzburg-Ziv theorem for finite groups
  • Tuan Tran, IBS Discrete Mathematics Group, The singularity of random combinatorial matrices

Due to COVID-19, the organizers decided to postpone the conference “Seymour is Seventy” to be held in Lyon, France, June 15-19, 2020

Due to COVID-19, the organizers decided to postpone the conference “Seymour is Seventy” to be held in Lyon, France, June 15-19, 2020. We hope to run a similar event in the summer of 2021 instead. Specific decisions on the dates are to be made when the situation clarifies.

Conference website:

The registration for the conference “Seymour is Seventy” (June 15-19) is now open! The deadline for early bird registration is April 12, 2020.

The registration for the conference “Seymour is Seventy” is now open.

  • Deadline for early bird registration : April 12, 2020.
  • Registration fees : 250 euros (includes coffee breaks, lunches, and the banquet)
  • For accompanying persons, it is possible to register only for the banquet for 70 euros
  • To register, follow the link from the website

The website also has a list of suggested hotels in Lyon.

Seymour is Seventy

A conference honouring the seventieth birthday of Paul Seymour
At ENS de Lyon, France
From June 15th to June 19th, 2020.

Invited speakers

Noga Alon, Princeton University / Tel Aviv University
Maria Chudnovsky, Princeton University
Julia Chuzhoy, Toyota Technological Institute at Chicago
Gérard Cornuéjols, Carnegie Mellon University
Matt DeVos, Simon Fraser University
Guoli Ding, Louisiana State University
Jacob Fox, Stanford University
Jim Geelen, University of Waterloo
András Gyárfás, Hungarian Academy of Sciences
Alexandr V. Kostochka, University of Illinois at Urbana-Champaign
Chun-Hung Liu, Texas A&M University
Sergey Norin, McGill University
Sang-il Oum, IBS Discrete Mathematics Group / KAIST
Bruce Reed, McGill University
Alexander Schrijver, University of Amsterdam / CWI Amsterdam
Alex Scott, University of Oxford
Sophie Spirkl, Princeton University
Benny Sudakov, ETH Zurich
Stéphan Thomassé, ENS de Lyon
Carsten Thomassen, Technical University of Denmark
Kristina Vušković, University of Leeds
Paul Wollan, University of Rome “La Sapienza”

IBS 이산수학그룹 Discrete Mathematics Group
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IBS Discrete Mathematics Group (DIMAG)
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