How can you tell two knots apart? It’s a tougher question than you might think. www.quantamagazine.org/a-powerful-n...

#New_arXiv_paper *Andreas Holmsen*, Attila Jung, Balázs Keszegh, Dániel G. Simon, and Gábor Tardos, Piercing all maximum cliques in hypergraphs, 2026. arxiv.org/abs/2604.21588

#New_accepted_conference_paper *Colin Geniet*, Fatemeh Ghasemi, and Mamadou Moustapha Kanté, Transducing Linear Decompositions of Tournaments, In the Proceedings of ICALP 2026 (Royal Holloway, University of London. London, UK, July 7-10), accepted, 2026. arxiv.org/abs/2601.02999

#New_arXiv_paper Édouard Bonnet, Yeonsu Chang, Julien Duron, *Colin Geniet*, and *O-joung Kwon*, Moderately beyond clique-width: reduced component max-leaf and related parameters, 2026. arxiv.org/abs/2604.19138

#New_accepted_conference_paper Édouard Bonnet, *Colin Geniet*, *Eun Jung Kim*, and Sungmin Moon, Fast shortest path in graphs with sparse signed tree models and applications, ICALP 2026 (Royal Holloway, University of London. London, UK, July 7-10), accepted, 2026. arxiv.org/abs/2602.06516

#New_accepted_conference_paper *Maximilian Gorsky*, Evangelos Protopapas and Sebastian Wiederrecht, Quickly excluding an annotated planar graph, In the Proceedings of ICALP 2026 (Royal Holloway, University of London. London, UK, July 7-10), accepted, 2026.

#New_accepted_conference_paper *Maximilian Gorsky*, Michał Seweryn, and Sebastian Wiederrecht, The price of homogeneity is polynomial, In the Proceedings of ICALP 2026 (Royal Holloway, University of London. London, UK, July 7-10), accepted, 2026.

#New_accepted_conference_paper *Mujin Choi*, *Maximilian Gorsky*, *Gunwoo Kim*, Caleb McFarland, and Sebastian Wiederrecht, Odd-Cycle-Packing-treewidth: On the Maximum Independent Set problem in odd-minor-free graph classes, In the Proceedings of ICALP 2026, London, UK, July 7-10), accepted, 2026.

Mamadou Moustapha Kanté gave a talk on characterizing strongly flip-flat graph classes without a large complete bipartite subgraph at the Discrete Math Seminar On April 7, 2026, Mamadou Moustapha Kanté from Université Clermont Auvergne gave a talk at the Discrete Math Seminar on characterizing…

Welcome Marguerite Bin, a new graduate student of the IBS Discrete Mathematics Group The IBS Discrete Mathematics Group welcomes Marguerite Bin, a new graduate student of the Discrete Mathematics Group from April 2, 2026 to May 26, 2026. She is a Ph.D. student at Université de Lorraine. Her…

Tung Nguyen gave a talk on polynomial 𝛘-boundedness of P_5-free graphs at the Discrete Math Seminar On March 31, 2026, Tung Nguyen from the University of Oxford gave a talk at the Discrete Math Seminar on polynomial 𝛘-boundedness of graphs with no induced path on 5 vertices. The title of his talk…

#New_accepted_paper Debsoumya Chakraborti, Minho Cho, *Jinha Kim*, and Minki Kim, Colorful fractional Helly theorem via weak saturation, Electron. J. Combin., accepted, 2026. arxiv.org/abs/2408.15093

4색 정리 새로운 증명이 arXiv에 올라왔습니다. New proof of the four color theorem by Yuta Inoue, Ken-ichi Kawarabayashi, Atsuyuki Miyashita, Bojan Mohar, Carsten Thomassen, Mikkel Thorup arxiv.org/abs/2603.24880

Hidde Koerts gave a talk on characterizing tournaments with no backedge graph of small clique number at the Discrete Math Seminar On March 24, 2026, Hidde Koerts from the University of Waterloo gave a talk at the Discrete Math Seminar on characterizing tournaments with no backedge graph of small…

#New_arXiv_paper Jakob Greilhuber and *Roohani Sharma*, A dividing line for structural kernelization of component order connectivity via distance to bounded pathwidth, 2026. arxiv.org/abs/2603.22240

#New_accepted_paper Seoyoung Kim, Chi Hoi Yip, and *Semin Yoo*, f-Diophantine sets over finite fields via quasi-random hypergraphs from multivariate polynomials, Mathematika, accepted, 2026. arxiv.org/abs/2503.19603

#New_accepted_paper Peter Bradshaw, *Ilkyoo Choi*, Alexandr Kostochka, and Jingwei Xu, A lower bound on the number of edges in DP-critical graphs, J. Combin. Theory Ser. B, accepted, 2026. arxiv.org/abs/2409.00937

József Balogh gave a talk on decomposing (or covering) the edge set of a graph into (or by) cliques at the Discrete Math Seminar On March 12, 2026, József Balogh from the University of Illinois at Urbana-Champaign gave a talk on decomposing the edge set of a graph into edge sets of clliques or…

#New_arXiv_paper *Sang-il Oum* and Marek Sokołowski, Polynomial-size encoding of all cuts of small value in integer-valued symmetric submodular functions, 2026. arxiv.org/abs/2603.10710

Dario Cavallaro gave a talk on well-quasi-ordering of Eulerian digraphs under (strong) immersion at the Discrete Math Seminar On March 10, 2026, Dario Cavallaro from the TU Berlin gave a talk at the Discrete Math Seminar on well-quasi-ordering of Eulerian digraphs under (strong) immersion. The…

As runners move around a track, are they bound to end up “lonely”? Three new proofs suggest the answer is yes — the first significant progress on the problem in decades. www.quantamagazine.org/new-strides-...

Chính T. Hoàng gave a survey talk on graph coloring and forbidden induced subgraphs at the Discrete Math Seminar On March 3, 2026, Chính T. Hoàng from the Wilfrid Laurier University, Waterloo, Canada gave a survey talk on graph coloring and… https://dimag.ibs.re.kr/2026/chinh-t-hoang-seminar/

#New_arXiv_paper Karolina Drabik, Maël Dumas, *Colin Geniet*, Jakub Nowakowski, Michał Pilipczuk, and Szymon Toruńczyk, Variants of Merge-Width and Applications, 2026. arxiv.org/abs/2602.23867

#New_accepted_paper Katie Clinch, Sean Dewar, Niloufar Fuladi, *Maximilian Gorsky*, *Tony Huynh*, Eleftherios Kastis, Atsuhiro Nakamoto, Anthony Nixon, and Brigitte Servatius, Triangulated spheres with holes in triangulated surfaces, Discrete Comput. Geom., accepted, 2026. arxiv.org/abs/2410.04450

#New_arXiv_paper Jorge Olivares-Vinales and *Semin Yoo*, Towers and Bratteli-Vershik systems in Fibonacci-like unimodal maps, 2026. arxiv.org/abs/2602.21623

#New_arXiv_paper Seoyoung Kim, Chi Hoi Yip, and *Semin Yoo*, Shifted multiplicative subgroups are not ratio sets, 2026. arxiv.org/abs/2602.20919

Marek Sokołowski gave a talk on a new parallel algorithm computing single-source shortest paths in directed graphs at the Discrete Math Seminar On February 24, 2026, Marek Sokołowski from the Max Planck Institute of Informatics gave a talk at… https://dimag.ibs.re.kr/2026/marek-sokolowski-seminar/

#New_arXiv_paper *Colin Geniet*, Aliénor Goubault-Larrecq, and Kévin Perrot, Complexity lower bounds for succinct binary structures of bounded clique-width with restrictions, 2026. arxiv.org/abs/2602.18240

#New_arXiv_paper Édouard Bonnet, *Colin Geniet*, *Eun Jung Kim*, and Sungmin Moon, Fast shortest path in graphs with sparse signed tree models and applications, 2026. arxiv.org/abs/2602.16605

#New_accepted_paper *O-joung Kwon* and Xiaopan Lian, On a variant of dichromatic number for digraphs with prescribed sets of arcs, Graphs and Combinatorics, accepted, 2026. arxiv.org/abs/2307.05897

Seonghun Park (박성훈) gave a talk on formalizing the flag algebra in the lean theorem prover On February 10, 2026, Seonghun Park (박성훈) from KAIST gave a talk on formalizing the flag algebra introduced by Alexander Razborov in the lean theorem… https://dimag.ibs.re.kr/2026/seonghun-park-flag-algebra/

#New_accepted_conference_paper *Colin Geniet*, *Gunwoo Kim*, and Lucas Meijer, First-Order Logic and Twin-Width for Some Geometric Graphs, In the Proceedings of the 42nd International Symposium on Computational Geometry (SoCG 2026), accepted, 2026. arxiv.org/abs/2512.21896

#New_arXiv_paper *Maximilian Gorsky* and Clemens Kuske, On non-planar, cycle-conformal graphs, 2026. arxiv.org/abs/2602.07331

Xiaofan Yuan gave a talk on the minimum color-degree condition for having a rainbow path at the Discrete Math Seminar On February 3, 2026, Xiaofan Yuan from the IBS Extremal Combinatorics and Probability Group gave a talk at the Discrete Math… https://dimag.ibs.re.kr/2026/xiaofan-yuan-rainbow/

#New_arXiv_paper *Maximilian Gorsky*, Michał T. Seweryn, and Sebastian Wiederrecht, The price of homogeneity is polynomial, 2026. arxiv.org/abs/2602.01882

#New_accepted_paper *Jungho Ahn*, *Jinha Kim*, and *O-joung Kwon*, Unified almost linear kernels for generalized covering and packing problems on nowhere dense classes, J. Comput. System Sci., accepted, 2026. arxiv.org/abs/2207.06660

Welcome Hyunsung Choi (최현성), a new graduate student of the IBS Discrete Mathematics Group The IBS Discrete Mathematics Group welcomes Hyunsung Choi (최현성), a new graduate student of the Discrete Mathematics Group from February 1, 2026. He received… http://dimag.ibs.re.kr/2026/welcome-hyunsung-choi/

#New_arXiv_paper Jiangdong Ai, Ming Chen, *Seokbeom Kim*, and Hyunwoo Lee, On a weaker notion of cross t-intersecting families, 2025. arxiv.org/abs/2601.20516

Daniel Dadush gave a talk on a strongly polynomial-time algorithm to solve linear programming problems with at most two non-zero entries per each row or each column at the Discrete Math Seminar On January 27, 2025, Daniel Dadush from CWI gave a… https://dimag.ibs.re.kr/2026/daniel-dadush-seminar/

#New_arXiv_paper Hyunwoo Lee, Chi Hoi Yip, and *Semin Yoo*, Product representations of polynomials over finite fields, 2025. arxiv.org/abs/2601.16657

“KAIST 학생이 직접 쓰려고 만든 AI 강의 필기앱 # 10,000시간을 써도 무료⏤ 서버, API 비용이 안들기 때문에 가능합니다. 결제도 안 붙였어요. # 로컬 AI⏤ 서버가 없기 때문에 인터넷이 필요없어요. # 철저한 보안⏤모든 내용은 사용자 PC에만 저장됩니다. # 실시간 번역“ www.altalt.io/ko

#New_arXiv_paper Chi Hoi Yip and *Semin Yoo*, Paley-type matrices and 1-factorizations of complete graphs, 2026. arxiv.org/abs/2601.12250

Tomáš Masařík gave a talk at the Discrete Math Seminar on finding a balanced separator in an H-minor-free graph in linear time On January 20, 2026, Tomáš Masařík from the University of Warsaw, Poland, gave a talk on a linear-time algorithm to… https://dimag.ibs.re.kr/2026/tomas-masarik-seminar/

#New_accepted_paper *O-joung Kwon* and Youngho Yoo, Erdős-Pósa property of A-paths in unoriented group-labelled graphs, Combinatorica, accepted, 2026. arxiv.org/abs/2411.05372

Ferdinand Ihringer gave a talk at the Discrete Math Seminar on low-degree Boolean functions and applications of vector space Ramsey numbers On January 13, 2026, Ferdinand Ihringer from the Southern University of Science and Technology, China gave a… https://dimag.ibs.re.kr/2026/ferdinand-ihringer/

#New_accepted_paper P. S. Ardra, R. Krithika, Saket Saurabh, and *Roohani Sharma*, Balanced Substructures in Bicolored Graphs, Theoret. Comput. Sci., accepted, 2026. doi.org/10.1016/j.tc...

#New_arXiv_paper *Colin Geniet* and Ugo Giocanti, Basis Number of Graphs Excluding Minors, 2026. arxiv.org/abs/2601.05195

#New_arXiv_paper Tuukka Korhonen and *Sang-il Oum*, Branch-width of connectivity functions is fixed-parameter tractable, 2026. arxiv.org/abs/2601.04756

Daniel Mock gave a talk at the Discrete Math Seminar on an algorithmic framework for showing the fixed-parameter tractability of the dominating set problem and its generalizations On January 6, 2026, Daniel Mock from RWTH Aachen gave a talk on an… https://dimag.ibs.re.kr/2026/daniel-mock/

#New_arXiv_paper *Colin Geniet*, Fatemeh Ghasemi, and Mamadou Moustapha Kanté, Transducing Linear Decompositions of Tournaments, 2025. arxiv.org/abs/2601.02999