Matchings in simplicial complexes, circuits and toric varieties
نویسندگان
چکیده
Using a generalized notion of matching in a simplicial complex and circuits of vector configurations, we compute lower bounds for the minimum number of generators, the binomial arithmetical rank and the A-homogeneous arithmetical rank of a lattice ideal. Prime lattice ideals are toric ideals, i.e. the defining ideals of toric varieties. © 2006 Elsevier Inc. All rights reserved.
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عنوان ژورنال:
- J. Comb. Theory, Ser. A
دوره 114 شماره
صفحات -
تاریخ انتشار 2007