Critical groups of graphs with dihedral actions
نویسندگان
چکیده
In this paper we consider the critical group of finite connected graphs which admit harmonic actions by the dihedral group Dn. In particular, we show that if the orbits of the Dn-action all have either n or 2n points then the critical group of such a graph can be decomposed in terms of the critical groups of the quotients of the graph by certain subgroups of the automorphism group. This is analogous to a theorem of Kani and Rosen which decomposes the Jacobians of algebraic curves with a Dn-action. © 2014 Elsevier Ltd. All rights reserved.
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عنوان ژورنال:
- Eur. J. Comb.
دوره 39 شماره
صفحات -
تاریخ انتشار 2014