Linear Inequalities for Rank 3 Geometric Lattices
نویسنده
چکیده
The flag Whitney numbers (also referred to as the flag f -numbers) of a geometric lattice count the number of chains of the lattice with elements having specified ranks. We give a collection of inequalities which imply all the linear inequalities satisfied by the flag Whitney numbers of rank 3 geometric lattices. We further describe the smallest closed convex set containing the flag Whitney numbers of rank 3 geometric lattices as well as the smallest closed convex set containing the flag Whitney numbers of those lattices corresponding to oriented matroids.
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ورودعنوان ژورنال:
- Discrete & Computational Geometry
دوره 31 شماره
صفحات -
تاریخ انتشار 2004