# 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…
18 Citations

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