Treewidth 2 in the Planar Graph Product Structure Theorem

Marc Distel, Kevin Hendrey, Nikolai Karol +2

We prove that every planar graph is contained in $H_1⊠H_2⊠K_2$ for some graphs $H_1$ and $H_2$ both with treewidth 2. This resolves a question of Liu, Norin and W…