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arXiv · 1001.3238

The cone of Betti diagrams of bigraded artinian modules of codimension two

Mats Boij·Gunnar Floystad
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Abstract

We describe the positive cone generated by bigraded Betti diagrams of artinian modules of codimension two, whose resolutions become pure of a given type when taking total degrees. If the differences of these total degrees, p and q, are relatively prime, the extremal rays are parametrised by order ideals in N^2 contained in the region px + qy < (p-1)(q-1). We also consider some examples concerning artinian modules of codimension three.

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Mats Boij, Gunnar Floystad. 2010-01-19. The cone of Betti diagrams of bigraded artinian modules of codimension two. https://doi.org/10.1007/978-3-642-19492-4

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