Abstract
We improve the undecidability bounds for problems involving two integer matrices by showing that Scalar Reachability, Zero in the Right Upper Corner, Vector Reachability, and Zero in the Left Upper Corner are undecidable for dimensions of 9, 10, 11, and 13, respectively. Problems Scalar Reachability, Zero in the Right Upper Corner, and Vector Reachability were previously known undecidable for dimensions 18, 18, and 16, respectively.
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The authors are supported by the Academy of Finland under grants 208414 and 208797, respectively.
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Halava, V., Hirvensalo, M. Improved matrix pair undecidability results. Acta Informatica 44, 191–205 (2007). https://doi.org/10.1007/s00236-007-0047-y
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DOI: https://doi.org/10.1007/s00236-007-0047-y