Linear colorings of simplicial complexes and collapsing

نویسندگان

  • Yusuf Civan
  • Ergün Yalçin
چکیده

A vertex coloring of a simplicial complex ∆ is called a linear coloring if it satisfies the property that for every pair of facets (F1, F2) of ∆, there exists no pair of vertices (v1, v2) with the same color such that v1 ∈ F1\F2 and v2 ∈ F2\F1. We show that every simplicial complex ∆ which is linearly colored with k colors includes a subcomplex ∆ with k vertices such that ∆ is a strong deformation retract of ∆. We also prove that this deformation is a nonevasive reduction, in particular, a collapsing.

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عنوان ژورنال:
  • J. Comb. Theory, Ser. A

دوره 114  شماره 

صفحات  -

تاریخ انتشار 2007