Midsummer Combinatorial Workshop XXVII

August 1 - 5, 2022, Prague

MCW 2023

Programme (tentative)

All lectures take place in room S5 at the building of Charles University, Malostranske namesti 25. The times are only indicative and are subject to change.
Morning Registration
9:00-9:15 Welcome, brief information about program of the workshop
9:15-10:00Andy ZuckerGalvin-Prikry theorems for big Ramsey structures
10:00-10:30Coffee break
10:30-11:05Václav RozhoňA Nearly Tight Analysis of Greedy k-means++
11:05-12:00Stevo TodorcevicA dual Ramsey theorem for trees
9:00-9:25Martin BalkoUNCE Day: Bounding and computing obstacle numbers of graphs
9:25-9:50Jakub BulínUNCE Day: Coloring oriented trees
9:50-10:15Pavel HubáčekUNCE Day: On the Complexity of Inefficient Proofs of Existence in Combinatorics
10:20-10:50Coffee break
10:50-11:15Sophia KeipKicherberger's Theorem for complexes of oriented matroids
11:20-11:40Tomáš HonsGadget construction for elementary convergence of relational structures
11:45-12:15Paulina RadeckaEvolution systems of (in)finite structures
9:00-9:30Jindrich ZapletalTwo graph games
9:33-10:00Nadav MeirModel theorists doing structural Ramsey theory
10:00-10:30Coffee break
10:30-11:15Noé de RancourtMetric big Ramsey degrees
11:20-12:15Marcin SabokMonochromatic sums and products in the rationals
Afternoon-∞Hike to Karlštejn and conference dinner in Pod Dračí skálou (starting at 18:00). We go there by train from Smíchovské nádraží (meeting at Smíchovské nádraží (Praha-Smíchov) before 14:15 or at the train station in front of the department before 13:55), details will be announced at the workshop.
9:00-9:30Dragan MašulovićEntropy from small Ramsey degrees
9:30-10:00Colin JahelA candidate counter-example for the unique ergodicity problem
10:00-10:30Coffee break
10:30-10:55Santiago Guzmán ProLocal expressions of hereditary classes
11:00-11:30Sam BraunfeldCounting siblings in hereditary classes
11:40-12:00Imane TalbaouiDoubly regular tournaments and the mesure of simplicity
12:00-12:47Andrés ArandaNew constructions for HH-homogeneous graphs
9:00-9:25Marta PavelkaFive non-Hamiltonian Simplicial complexes
9:30-10:00Misha TyomkynMonochromatic connected components
10:00-10:30Coffee break
10:30-10:55Lluis VenaA homomorphism notion of maps and its poset of cores
11:00-11:20Vahideh KeikhaOn color spanning circles of colored disks
11:25-11:55Andrew GoodallA tale of two 4-term relations


The workshop continues the tradition of Prague Combinatorial Workshops held since 1993. Oriented on problems of all fields of graph theory, combinatorics and discrete geometry, it will continue in the spirit and informal working atmosphere of the previous meetings.

The workshop takes place at DIMATIA and the Department of Applied Mathematics of Charles University, Malostranske namesti 25, Prague 1, which is located in a historic building in the center of Old Prague. The workshop is also supported by Computer Science Institute of Charles University.

The workshop participation is by invitation only. Regardless, if you wish to participate, please email the organizers and we will respond to you shortly. In case you need an invitation letter (for example for your visa), please let us know and we will be happy to write one for you.

Coffee breaks and part of the meals are provided by the organizers. However, we will collect a modest fee of EUR 80 towards a fraction of the expenses.

As is the tradition, the program of the workshop is determined from day to day. The afternoons are reserved for discussions and other activities. If you intend to give a talk during the MCW, please let us know a few days in advance.

If you arrive later during the workshop, please register with the secretaries in the room 222 (at the 2nd floor).

On Wednesday afternoon, there will be an awesome social event.

This workshop is part of a project that has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No 810115)


Besides the workshop itself, you are free to use the following facilities of our departments:

  • Two open lounges with tables, chairs and a whiteboard opposite the Lecture Room S5. You can take the lounges on a first come, first serve basis. Great for working on open problems in the afternoon!
  • Two open lounges with tables, chairs and a whiteboard on the third floor, directly above the lounges on the second floor. Same rules apply.
  • Water coolers in the hall with the open lounges -- both on second and third floor.

If you need anything else, contact the organizers.

Travel info (public transport)

For the public transportation you can buy a 90-minute ticket for 40 CZK or 30-minute for 30 CZK in a newsstand or in a vending machine. Some vending machines only accept coins (no credit cards, no paper money).

The ticket needs to be validated (in a magic yellow validating machine with a shining arrow). The validating machines are located inside buses and trams. In the Metro subway system, the machine is located at the entryway to the station.

If you need to find a tram connection, you can use the official website. The department building is located near the tram stop "Malostranske namesti". You can see it from the tram stop. It is this building.

Useful routes:

Airport -> Karolinum Hotel

  • From airport to Karolinum take bus number 119 to Nadrazi Veleslavin station (last stop).
  • Transfer to Metro subway A (green line) and take it to the station Staromestska.
  • Exit the subway and continue on foot:

Airport -> Karolinum Hotel

  • From airport to Karolinum take bus number 119 to Nadrazi Veleslavin station (last stop).
  • Transfer to Metro subway A (green line) and take it to the station Staromestska.
  • Exit the subway and continue on foot:
  • Take the Kaprova street to the Old Town Square.
  • From the Old Town Square go through the Celetna street to your hotel.

Karolinum Hotel -> MCW

  • Walk to the Subway station Staromestska.
  • Take the Metro subway line A (direction: Nemocnice Motol) to Malostranska.
  • Exit the subway at Malostranska and take one stop with any of the following trams: 12, 15 or 20 to Malostranske namesti.


All e-mail correspondence concerning the workshop (e.g. registration, accommodation) should be directed to mcw@@kam.mff.cuni.cz.

organizers: Jaroslav Nesetril, Jan Hubicka, Matej Konecny

Previous Workshops