• Compressing permutation groups into grammars and polytopes. A graph embedding approach 

      Jaffke, Lars; De Oliveira Oliveira, Mateus; Tiwary, Hans Raj (Journal article; Peer reviewed, 2020)
      It can be shown that each permutation group G ⊑ 𝕊_n can be embedded, in a well defined sense, in a connected graph with O(n+|G|) vertices. Some groups, however, require much fewer vertices. For instance, 𝕊_n itself can ...
    • Width Notions for Ordering-Related Problems 

      Arrighi, Emmanuel; Fernau, Henning; De Oliveira Oliveira, Mateus; Wolf, Petra (Journal article; Peer reviewed, 2020)
      We are studying a weighted version of a linear extension problem, given some finite partial order ρ, called Completion of an Ordering. While this problem is NP-complete, we show that it lies in FPT when parameterized by ...