Enumerating branched coverings over surfaces with boundaries
نویسندگان
چکیده
The number of nonisomorphic n-fold branched coverings over a given surface with a boundary is determined by the number of nonisomorphic n-fold graph coverings over a suitable bouquet of circles. A similar enumeration can be done for regular branched coverings. Some explicit formulae for enumerations are also obtained. © 2003 Elsevier Ltd. All rights reserved. MSC 2000: 05C10; 05C30; 57M12
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عنوان ژورنال:
- Eur. J. Comb.
دوره 25 شماره
صفحات -
تاریخ انتشار 2004