Saturation points on faces of a rational polyhedral cone

  title={Saturation points on faces of a rational polyhedral cone},
  author={Akimichi Takemura and Ruriko Yoshida},
  journal={arXiv: Combinatorics},
Different commutative semigroups may have a common saturation. We consider distinguishing semigroups with a common saturation based on their ``sparsity''. We propose to qualitatively describe sparsity of a semigroup by considering which faces of the corresponding rational polyhedral cone have saturation points. For a commutative semigroup we give a necessary and sufficient condition for determining which faces have saturation points. We also show that we can construct a commutative semigroup… 

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