Unimodality of Eulerian quasisymmetric functions
نویسندگان
چکیده
We prove two conjectures of Shareshian and Wachs about Eulerian quasisymmetric functions and polynomials. The first states that the cycle type Eulerian quasisymmetric function Qλ,j is Schur-positive, and moreover that the sequence Qλ,j as j varies is Schur-unimodal. The second conjecture, which we prove using the first, states that the cycle type (q, p)-Eulerian polynomial A λ (q, p, q −1t) is t-unimodal.
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. A
دوره 119 شماره
صفحات -
تاریخ انتشار 2012