10 papers
Interval Deformations of Coxeter Arrangements
Yanru Chen, Ang Li, Suijie Wang
We study integer-interval deformations of Coxeter arrangements of types , , and , assigning an integer interval to each root direction through an integer-valued root funct…
Log-Concavity of Conic Intrinsic Volumes
Houshan Fu, Suijie Wang
Let and be a closed convex cone with conic intrinsic volumes . We prove the long-standing log-concavity conjecture for this s…
Characteristic Polynomials of Graph- and Digraph-Deleted Catalan Arrangements
Yanru Chen, Ang Li, Suijie Wang
We develop a finite-field stratification for characteristic polynomials of deletion subarrangements of the full -Catalan arrangement. It reduces the count to cyclic placements o…
Convolution-type Identity for Characteristic Polynomials of Geometric Semilattices
Yanru Chen, Houshan Fu, Ang Li +1
We establish a convolution formula for the characteristic polynomial of a finite geometric semilattice : \[ χ(M,st)=\sum_{X\in \underline{M}} s^{r-{\rm rk}_{\underline{M}}(X)}χ(…
A decomposition of Grassmannian associated with a hyperplane arrangement
Houshan Fu, Weikang Liang, Suijie Wang
The Grassmannian, which is the manifold of all -dimensional subspaces in the Euclidean space , was decomposed through three equivalent methods connecting combinato…
Level of Regions for Deformed Braid Arrangements
Yanru Chen, Houshan Fu, Suijie Wang +1
This paper primarily investigates a specific type of deformation of the braid arrangement in , denoted by and defined in (1.2). Let…
Level Decompositions for Symmetric Deformations of the Braid Arrangement
Yanru Chen, Suijie Wang, Jinxing Yang +1
Let be finite and nonempty, and let be the associated sequence of symmetric deformations of t…
Counting Flows of -compatible Graphs
Houshan Fu, Xiangyu Ren, Suijie Wang
Kochol introduced the assigning polynomial to count nowhere-zero -flows of a graph , where is a finite Abelian group and is a -assigning from…
Two Bijections on NBC Subsets
Houshan Fu, Baoren Peng, Suijie Wang +1
We establish two explicit bijections: from acyclic reorientations of an oriented matroid to no broken circuit (NBC) subsets of its underlying matroid, and from regions of a real hy…
Deformed Intersections of Half-spaces
Houshan Fu, Boxuan Li, Chunming Tang +1
This paper is devoted to the classification problems concerning extended deformations of convex polyhedra and real hyperplane arrangements in the following senses: combinatorial eq…