Title
Irrational proofs for three theorems of Stanley
Abstract
We give new proofs of three theorems of Stanley on generating functions for the integer points in rational cones. The first relates the rational generating function σv+K(x) := Σm∈(v+K)∩ZdXm, where K is a rational cone and v ∈Rd, with σ-v+K°(1/x). The second theorem asserts that the generating function 1+Σn≥1LP(n)tn of the Ehrhart quasi-polynomial LP(n) := #(nP∩Zd) of a rational polytope P can be written as a rational function vP(t)/(1-t)dimP+1 with nonnegative numerator vP. The third theorem asserts that if P ⊆ Q, then vP ≤ vQ. Our proofs are based on elementary counting afforded by irrational decompositions of rational polyhedra.
Year
DOI
Venue
2007
10.1016/j.ejc.2005.06.003
Eur. J. Comb.
Keywords
Field
DocType
rational polyhedron,rational generating function,nonnegative numerator vp,rational cone,ehrhart quasi-polynomial lp,generating function,irrational decomposition,rational function vp,rational polytope,integer point,irrational proof,rational function
Integer,Discrete mathematics,Generating function,Combinatorics,Polyhedron,Irrational number,Mathematical proof,Polytope,Rational function,Fraction (mathematics),Mathematics
Journal
Volume
Issue
ISSN
28
1
European Journal of Combinatorics 28, no. 1 (2007), 403-409
Citations 
PageRank 
References 
12
1.51
1
Authors
2
Name
Order
Citations
PageRank
Matthias Beck15410.27
Frank Sottile2265.10