Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Fixed Points of Maps of a Nonaspherical Wedge | Hindawi Publishing Corporation Fixed Point Theory and Applications Volume 2009 Article ID 531037 18 pages doi 2009 531037 Research Article Fixed Points of Maps of a Nonaspherical Wedge Seung Won Kim 1 Robert F. Brown 2 Adam Ericksen 3 Nirattaya Khamsemanan 4 and Keith Merrill5 1 Department of Mathematics College of Science Kyungsung University Busan 608-736 South Korea 2 Department of Mathematics University of California Los Angeles CA 90095 USA 3 Department of Mathematics University of Southern California Los Angeles CA 90089 USA 4 Sirindhorn International Institute of Technology Thammasat University Pathum Thani 12121 Thailand 5 Department of Mathematics Brandeis University Belmont MA 02453 USA Correspondence should be addressed to Seung Won Kim kimsw@ Received 4 September 2008 Accepted 13 January 2009 Recommended by Evelyn Hart Let X be a finite polyhedron that has the homotopy type of the wedge of the projective plane and the circle. With the aid of techniques from combinatorial group theory we obtain formulas for the Nielsen numbers of the selfmaps of X. Copyright 2009 Seung Won Kim et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. Introduction Although compact surfaces were the setting of Nielsen s fixed point theory in 1927 1 until relatively recently the calculation of the Nielsen number was restricted to maps of very few surfaces. For surfaces with boundary such calculations were possible on the annulus and Mobius band because they have the homotopy type of the circle. In 1987 2 Kelly used the commutativity property of the Nielsen number to make calculations for a family of maps of the disc with two holes. We will discuss Kelly s technique in more detail below. The first general algorithm for calculating Nielsen numbers of maps of surfaces with boundary was published by .
