# 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} }

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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