Graph theory, simplicial complex Four Forests Fit By oliverknill October 8, 2023 October 8, 2023 arboricity This is a complement to the Three Trees Theorem: For any non-sphere surface, the arboricity is 4. Screenshot Screenshot Screenshot Screenshot Screenshot Screenshot Screenshot Screenshot Screenshot Screenshot Screenshot Screenshot Screenshot Author: oliverknill I'm a mathematician working in Cambridge, MA. View all posts by oliverknill → Arboricity of Surfaces Trees on 3-manifolds