The largest demigenus of a bipartite signed graph
نویسنده
چکیده
A graph with signed edges is orientation embedded in a surface when it is topologically embedded so that one trip around a closed path preserves or reverses orientation according as the path's sign product is positive or negative. We nd the smallest surface within which it is possible to orientation-embed the complete bipartite signed graph K r;s , which is obtained from the complete bipartite graph K r;s through replacing each edge by two parallel edges, one positive and the other negative. Introduction and Theorems Given: a bipartite graph ? (multiple edges allowed) and a list L, possibly empty, of polygons (graphs of simple closed paths in ?). Wanted: the smallest possible surface
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 232 شماره
صفحات -
تاریخ انتشار 2001