4 papers
Cyclically Compatible Deformations of the Braid Arrangement
Yanru Chen, Ang Li, Suijie Wang
We prove a characteristic-polynomial shift formula for two-sided extensions of cyclically compatible deformations of the braid arrangement. For a nonnegative integer matrix $M=(m_{…
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(…
On the Steenrod module structure of -motivic Spanier-Whitehead duals
Prasit Bhattacharya, Bertrand J. Guillou, Ang Li
The -motivic cohomology of an -motivic spectrum is a module over the -motivic Steenrod algebra . In this paper, we des…