English

On Brylawski's generalized duality

Combinatorics 2012-01-10 v1

Abstract

We introduce a notion of duality (due to Brylawski) that generalizes matroid duality to arbitrary rank functions. This generalized duality allows for generalized operations (deletion and contraction) and a generalized polynomial based on the matroid Tutte polynomial. This polynomial satisfies a deletion-contraction recursion. We explore this notion of duality for greedoids, antimatroids and demi-matroids, proving that matroids correspond precisely to objects that are simultaneously greedoids and "dual" greedoids.

Keywords

Cite

@article{arxiv.1201.1831,
  title  = {On Brylawski's generalized duality},
  author = {Gary Gordon},
  journal= {arXiv preprint arXiv:1201.1831},
  year   = {2012}
}
R2 v1 2026-06-21T20:02:10.923Z