The Γ-vector of a Barycentric Subdivision
نویسندگان
چکیده
We prove that the γ-vector of the barycentric subdivision of a simplicial sphere is the f -vector of a balanced simplicial complex. The combinatorial basis for this work is the study of certain refinements of Eulerian numbers used by Brenti and Welker to describe the h-vector of the barycentric subdivision of a boolean complex.
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