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q-analogues of Ehrhart polynomials

Published online by Cambridge University Press:  17 December 2015

F. Chapoton*
Affiliation:
Institut Camille Jordan, Université Claude Bernard Lyon 1, Bâtiment Braconnier, 21 Avenue Claude Bernard, 69622 Villeurbanne Cedex, France ([email protected])

Abstract

We consider weighted sums over points of lattice polytopes, where the weight of a point v is the monomial qλ(v) for some linear form λ. We propose a q-analogue of the classical theory of Ehrhart series and Ehrhart polynomials, including Ehrhart reciprocity and involving evaluation at the q-integers. The main novelty is the proposal to consider q-Ehrhart polynomials. This general theory is then applied to the special case of order polytopes associated with partially ordered sets. Some more specific properties are described in the case of empty polytopes.

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 2016 

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References

1. Apostol, T. M., An elementary view of Euler’s summation formula, Am. Math. Mon. 106(5) (1999), 409418.Google Scholar
2. Barvinok, A. and Pommersheim, J. E., An algorithmic theory of lattice points in polyhedra, in New perspectives in algebraic combinatorics, Mathematical Sciences Research Institute Publications, Volume 38, pp. 91147 (Cambridge University Press, 1999).Google Scholar
3. Beck, M., Combinatorial reciprocity theorems, Jahresber. Dtsch. Math.-Verein. 114(1) (2012), 322.Google Scholar
4. Beck, M. and Robins, S., Computing the continuous discretely: integer-point enumeration in polyhedra, Undergraduate Texts in Mathematics (Springer, 2007).Google Scholar
5. Brion, M., Points entiers dans les polyèdres convexes, Annales Scient. Éc. Norm. Sup. 21 (1988), 653663.Google Scholar
6. Brion, M., Points entiers dans les polytopes convexes, Exp. 780, in Séminaire Bourbaki, Astérique, Volume 36 (19931994), pp. 145169 (Société Mathématique de France, Paris, 1995).Google Scholar
7. Carlitz, L., q-Bernoulli numbers and polynomials, Duke Math. J. 15 (1948), 9871000.CrossRefGoogle Scholar
8. Chapoton, F., Sur une série en arbres à deux paramètres, Sém. Lotharingien Combinat. 70, Available at www.emis.de/journals/SLC/ (in French; 2013).Google Scholar
9. Ehrhart, E., Sur les polyèdres rationnels homothétiques à n dimensions, C. R. Acad. Sci. Paris Sér. I 254 (1962), 616618 (in French).Google Scholar
10. Féray, V. and Reiner, V., P-partitions revisited, J. Commut. Alg. 4(1) (2012), 101152.Google Scholar
11. Hahn, W., Über Orthogonalpolynome, die q-Differenzengleichungen genuügen, Math. Nachr. 2 (1949), 434.Google Scholar
12. Proctor, R. A., Bruhat lattices, plane partition generating functions, and minuscule representations, Eur. J. Combin. 5(4) (1984), 331350.Google Scholar
13. Stanley, R. P., Ordered structures and partitions, Memoirs of the American Mathematical Society, Volume 119 (American Mathematical Society, Providence, RI, 1972).Google Scholar
14. Stanley, R. P., Decompositions of rational convex polytopes, Annals Disc. Math. 6 (1980), 333342.Google Scholar
15. Stanley, R. P., Two poset polytopes, Discrete Comput. Geom. 1(1) (1986), 923.CrossRefGoogle Scholar
16. Stein, W. A. et al., Sage Mathematics Software, Version 5.10, The Sage Development Team, Available at www.sagemath.org (2013).Google Scholar
17. Stembridge, J. R., On minuscule representations, plane partitions and involutions in complex Lie groups, Duke Math. J. 73(2) (1994), 469490.Google Scholar
18. The Sage-Combinat community, Sage-Combinat: enhancing Sage as a toolbox for computer exploration in algebraic combinatorics, Available at http://combinat.sagemath.org (2008).Google Scholar