Delta-matroids as subsystems of sequences of Higgs lifts
نویسندگان
چکیده
In [30], Tardos studied special delta-matroids obtained from sequences of Higgs lifts; these are the full lift that we treat and around which all our results revolve. We give an excluded-minor characterization class within delta-matroids, similar characterizations two other minor-closed classes define using lifts. introduce a minor-closed, dual-closed arise lattice paths. It follows Bouchet can be by removing certain feasible sets; to address sets removed, more general structure set systems. Many excluded minors occur again when characterize in collection is union collections bases matroids different ranks, yet require those have properties, such as being paving.
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ژورنال
عنوان ژورنال: Advances in Applied Mathematics
سال: 2021
ISSN: ['1090-2074', '0196-8858']
DOI: https://doi.org/10.1016/j.aam.2019.04.007