Composition of regular coverings of graphs and voltage assignments
نویسنده
چکیده
Consider a composition of two regular coverings π1 : Γ0 → Γ1 and π2 : Γ1 → Γ2 of graphs, given by voltage assignments α1, α2 on Γ1, Γ2 in groups G1 and G2, respectively. In the case when π2 ◦ π1 is regular we present an explicit voltage assignment description of the composition in terms of G1, G2, α1, α2, and walks in Γ1.
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ورودعنوان ژورنال:
- Australasian J. Combinatorics
دوره 28 شماره
صفحات -
تاریخ انتشار 2003