The forbidden minor characterization of line-search antimatroids of rooted digraphs
نویسندگان
چکیده
An antimatroid is an accessible union-closed family of subsets of a 0nite set. A number of classes of antimatroids are closed under taking minors such as point-search antimatroids of rooted (di)graphs, line-search antimatroids of rooted (di)graphs, shelling antimatroids of rooted trees, shelling antimatroids of posets, etc. The forbidden minor characterizations are known for point-search antimatroids of rooted (di)graphs, shelling antimatroids of rooted trees and shelling antimatroids of posets. In this paper, we give the forbidden minor characterization of line-search antimatroids of rooted digraphs. ? 2002 Elsevier B.V. All rights reserved.
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ورودعنوان ژورنال:
- Discrete Applied Mathematics
دوره 131 شماره
صفحات -
تاریخ انتشار 2003