4 papers · 1 filter
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…
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(…
Level of Faces for Exponential Sequence of Arrangements
Yanru Chen, Houshan Fu, Weikang Liang +1
In this paper, we introduce the bivariate exponential generating function for the number of level- faces of an exponential sequence of arrangements (ESA), and establi…