A Combinatorial Reciprocity Theorem for Hyperplane Arrangements

Abstract

AbstractGiven a nonnegative integer m and a finite collection of linear forms on ℚd, the arrangement of affine hyperplanes in ℚd defined by the equations α(x) = k for α ∈ and integers k ∈ [–m,m] is denoted by . It is proved that the coefficients of the characteristic polynomial of are quasi-polynomials in m and that they satisfy a simple combinatorial reciprocity law.