Base-sortable Matroids and Koszulness of Semigroup Rings

@article{Blum2001BasesortableMA,
  title={Base-sortable Matroids and Koszulness of Semigroup Rings},
  author={Stefan Blum},
  journal={Eur. J. Comb.},
  year={2001},
  volume={22},
  pages={937-951}
}
  • Stefan Blum
  • Published 1 October 2001
  • Computer Science, Mathematics
  • Eur. J. Comb.
Motivated by a question in commutative algebra and inspired by the work of Sturmfels, we introduce the class of base-sortable matroids and show that it is closed under several matroid operations. All matroids of rank 2 are base-sortable and we give a characterization of base-sortability by excluded minors in the case of graphic matroids and rank 3 matroids. Transversal matroids with certain presentations are also base-sortable. For a base-sortable matroid M, the basis monomial ring RMis shown… 
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