2004/09/28 by Matthias Beck, Beck, Matthias, Mike Develin +1
Computer Science · Mathematics · #Advanced Combinatorial Mathematics #History and Theory of Mathematics #math.CO #msc:05A15 #msc:52C07 #semigroups and automata theory
paper · pdf · doi:10.48550/arxiv.math/0409562
9 pages
arxiv created 2005/08/04 · arxiv updated 2009/12/01
We give a short, self-contained proof of Stanley's reciprocity theorem for a rational cone K ⊂ Rd. Namely, let sigmaK (x) = summ ∈ K ∩ Zd xm. Then sigmaK (x) and sigmaint(K) (x) are rational functions which satisfy the identity sigmaK (1/x) = (-1)d sigmaint(K) (x). A corollary of Stanley's theorem is the Ehrhart-Macdonald reciprocity theorem for the lattice-point enumerator of rational polytopes. A distinguishing feature of our proof is that it uses neither the shelling of a polyhedron nor the concept of finite additive measures. The proof follows from elementary techniques in contour integration.