The forbidden minor characterization of line-search antimatroids of rooted digraphs

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The forbidden minor characterization of line-search antimatroids of rooted digraphs

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 antima...

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ژورنال

عنوان ژورنال: Discrete Applied Mathematics

سال: 2003

ISSN: 0166-218X

DOI: 10.1016/s0166-218x(02)00471-7