Philip Lilien

Regular-Closed Flats of Matroids: Cocircuit Reconstruction, Reconstruction Defect, and Finite Obstruction Hierarchies

Matroid theory is naturally a theory of closure. A matroid M on ground set E determines a closure operatorcl_M:2^E→2^E,and the flats of M are precisely its closed sets.Once a closure operator is present, however, a second standard construction becomes available. One may define an...

Regular-Closed Flats of Matroids: Cocircuit Reconstruction, Reconstruction Defect, and Finite Obstruction Hierarchies

Matroid theory is naturally a theory of closure. A matroid M on ground set E determines a closure operatorcl_M:2^E→2^E,and the flats of M are precisely its closed sets.Once a closure operator is present, however, a second standard construction becomes available. One may define an...