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arXiv · 1807.02432

Freeness of Hyperplane Arrangements between Boolean Arrangements and Weyl Arrangements of Type $ B_{\ell} $

Michele Torielli·Shuhei Tsujie
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Abstract

Every subarrangement of Weyl arrangements of type $ B_{\ell} $ is represented by a signed graph. Edelman and Reiner characterized freeness of subarrangements between type $ A_{\ell-1} $ and type $ B_{\ell} $ in terms of graphs. Recently, Suyama and the authors characterized freeness for subarrangements containing Boolean arrangements satisfying a certain condition. This article is a sequel to the previous work. Namely, we give a complete characterization for freeness of arrangements between Boolean arrangements and Weyl arrangements of type $ B_{\ell} $ in terms of graphs.

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Michele Torielli, Shuhei Tsujie. 2020-02-03. Freeness of Hyperplane Arrangements between Boolean Arrangements and Weyl Arrangements of Type $ B_{\ell} $. https://doi.org/10.37236/9341

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