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                * Princeton Discrete Math Seminar *
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Speaker: Nicolas Trotignon (ENS Lyon)

Thursday 26th March, 3:00 online at https://princeton.zoom.us/j/810888723

Title : Rankwidth, graphs on four vertices, and even holes

Abstract : Jointly with Hoang, we proved that there exist graphs of arbitrarily
large rankwidth that can be partitioned into three cliques, such that in
each clique, vertices are linearly ordered by the inclusion relation on their
neighborhood. During the talk, we will recall what rankwidth is, and describe
the construction. The end of the talk will be devoted to explaining how this
construction helps to understand several problems, such as coloring when 
a graph on four vertices is excluded as an induced subgraph, and the structure 
of even-hole-free-graphs. 


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Next week: TBA

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