Twisted Incidence Algebras and Kazhdan-Lusztig-Stanley functions
نویسنده
چکیده
We introduce a new multiplication in the incidence algebra of a partially ordered set, and study the resulting algebra. As an application of the properties of this algebra we obtain a combinatorial formula for the Kazhdan-Lusztig-Stanley functions of a poset. As special cases this yields new combinatorial formulas for the parabolic and inverse parabolic Kazhdan-Lusztig polyno-mials, for the generalized (toric) h-vector of an Eulerian poset, and for the Lusztig-Vogan polynomials.
منابع مشابه
Kazhdan-Lusztig-Stanley polynomials and quadratic algebras I M.J.Dyer
In [KL], Kazhdan and Lusztig associate a polynomial to each Bruhat interval in a Coxeter group; some of these “Kazhdan-Lusztig” polynomials now play an important role in several areas of representation theory. A similar family of polynomials has been associated to face latices of convex polytopes (see Stanley [St]). Both families of polynomials remain poorly understood in general, though they a...
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