On the Charney-Davis and Neggers-Stanley conjectures
نویسندگان
چکیده
For a graded naturally labelled poset P , it is shown that the P -Eulerian polynomial
منابع مشابه
Counterexamples to the Poset Conjectures of Neggers, Stanley, and Stembridge
We provide the first counterexamples to Neggers’ 1978 conjecture and Stembridge’s 1997 conjecture that the generating functions for descents and peaks in the linear extensions of naturally labeled posets should have all real zeros. We also provide minimum-sized counterexamples to a generalization of the Neggers conjecture due to Stanley that was recently disproved by Brändén.
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عنوان ژورنال:
- J. Comb. Theory, Ser. A
دوره 109 شماره
صفحات -
تاریخ انتشار 2005