Multiplicities of edge subrings
نویسندگان
چکیده
For a bipartite graph G we are able to characterize the complete intersection property of the edge subring in terms of the multiplicity and we give optimal bounds for this number. We give a method to obtain a regular sequence for the atomic ideal of G, when G is embedded on an orientable surface. We also give a graph theoretical condition for the edge subring associated with G to be Gorenstein. Finally we give a formula for the multiplicity of edge subrings, of arbitrary simple graphs. © 2005 Elsevier B.V. All rights reserved. MSC: Primary 13H10; Secondary 13F20, 13P10
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عنوان ژورنال:
- Discrete Mathematics
دوره 302 شماره
صفحات -
تاریخ انتشار 2005