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TOPOLOGICAL PROPERTIES OF GRAPHICAL ARRANGEMENTS

Nguyen, Thi A.;Kim, Sangwook

  • Received : 2014.04.03
  • Accepted : 2014.05.28
  • Published : 2014.06.25

Abstract

We show that for any graph G, the proper part of the intersection poset of the corresponding graphical arrangement $\mathcal{A}_G$ has the homotopy type of a wedge of spheres. Furthermore, we also indicate the number of spheres in the wedge, based on the number of spanning forests of G and other graphs that are obtained from G.

Keywords

graphical arrangement;EL-shallablity

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Acknowledgement

Supported by : National Research Foundation of Korea(NRF)