Reachability in 3-VASS is in Tower
The reachability problem for vector addition systems with states (VASS) has been shown to be Ackermann-complete. For every k≥ 3, a completeness result for the k-dimensional VASS reachability problem is not yet available. It is shown in this paper that the 3-dimensional VASS reachability problem is in Tower, improving upon the current best upper bound 𝐅_7 established by Leroux and Schmidt in 2019.
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