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arXiv · 1810.03518

Koszulness and supersolvability for Dirichlet arrangements

Bob Lutz
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Abstract

We prove that the cone over a Dirichlet arrangement is supersolvable if and only if its Orlik-Solomon algebra is Koszul. This was previously shown for four other classes of arrangements. We exhibit an infinite family of cones over Dirichlet arrangements that are combinatorially distinct from these other four classes.

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Bob Lutz. 2018-10-08. Koszulness and supersolvability for Dirichlet arrangements. https://doi.org/10.1090/proc%2F14591

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