Classification of Ehrhart polynomials of integral simplices
نویسنده
چکیده
Let δ(P) = (δ0, δ1, . . . , δd) be the δ-vector of an integral convex polytope P of dimension d. First, by using two well-known inequalities on δ-vectors, we classify the possible δ-vectors with ∑d i=0 δi ≤ 3. Moreover, by means of Hermite normal forms of square matrices, we also classify the possible δ-vectors with ∑d i=0 δi = 4. In addition, for ∑d i=0 δi ≥ 5, we characterize the δ-vectors of integral simplices when ∑d i=0 δi is prime. Résumé. Soit δ(P) = (δ0, δ1, . . . , δd) le δ-vecteur d’un polytope intégrante de dimension d. Tout d’abord, en utilisant deux bien connus des inégalités sur δ-vecteurs, nous classons les δ-vecteurs possibles avec ∑d i=0 δi ≤ 3. En outre, par le biais de Hermite formes normales, nous avons également classer les δ-vecteurs avec ∑d i=0 δi = 4. De plus, pour ∑d i=0 δi ≥ 5, nous caractérisons les δ-vecteurs des simplex inégalités lorsque ∑d i=0 δi est premier.
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