Séminaire Lotharingien de Combinatoire 54A (2006), Article B54Ae SYMMETRY AND UNIMODALITY IN THE q, x, y-HIT NUMBERS
نویسنده
چکیده
We prove symmetry, and in some cases symmetry and unimodality, of polynomials related to the q, x, y-hit numbers introduced by Haglund. These results generalize theorems proven by Haglund for the q-hit numbers. We also apply one of these results to obtain a corollary concerning a generalization of the Eulerian numbers. Résumé. Nous prouvons la symétrie et dans certains cas la symétrie et l’unimodalité des polynômes relatifs aux q, x, y nombres de contacts introduits par Haglund, généralisant ainsi certains théorèmes. Un de ces résultats nous permet d’obtenir un corollaire à propos d’une généralisation des nombres Eulériens.
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