Characterizing planarity using theta graphs
نویسندگان
چکیده
A theta graph is a homeomorph of K 2;3. In an embedded planar graph the local rotation at one degree-three vertex of a theta graph determines the local rotation at the other degree-three vertex. Using this observation, we give a characterization of planar graphs in terms of balance in an associated signed graph whose vertices are K 1;3 sub-graphs and whose edges correspond to theta graphs.
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ورودعنوان ژورنال:
- Journal of Graph Theory
دوره 27 شماره
صفحات -
تاریخ انتشار 1998