Raul Lopes

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3 papers · 1 filter

math.CO2026

Clique number of tournaments

Pierre Aboulker, Guillaume Aubian, Pierre Charbit +1

Given a digraph $D$ together with an ordering $≺$ of its vertices, the \emph{backedge graph} of $D$ with respect to $≺$ is the undirected graph $D^{≺}$ with the same ve…

math.CO2026

Finding forest-orderings of tournaments is NP-complete

Pierre Aboulker, Guillaume Aubian, Raul Lopes

Given a class of (undirected) graphs $C$ , we say that a Feedback Arc Set (FAS for short) $F$ is a $C$ -FAS if the graph induced by the edges of $F$ (forgetting t…

math.CO2024

Blow-ups and extensions of trees in tournaments

A class of acyclic digraphs $C$ is linearly unavoidable if there exists a constant $c$ such that every digraph $D \in C$ is contained in all tournaments of order…