Twin-width VIII: delineation and win-wins

  title={Twin-width VIII: delineation and win-wins},
  author={{\'E}douard Bonnet and Dibyayan Chakraborty and Eun Jung Kim and Noleen K{\"o}hler and Raul Lopes and St{\'e}phan Thomass{\'e}},
We introduce the notion of delineation. A graph class C is said delineated by twin-width (or simply, delineated ) if for every hereditary closure D of a subclass of C , it holds that D has bounded twin-width if and only if D is monadically dependent. An effective strengthening of delineation for a class C implies that tractable FO model checking on C is perfectly understood: On hereditary closures D of subclasses of C , FO model checking is fixed-parameter tractable (FPT) exactly when D has… 

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