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Structure of the Malvenuto-Reutenauer Hopf algebra of permutations (Extended Abstract)

Marcelo Aguiar·Frank Sottile
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Abstract

We analyze the structure of the Malvenuto-Reutenauer Hopf algebra of permutations in detail. We give explicit formulas for its antipode, prove that it is a cofree coalgebra, determine its primitive elements and its coradical filtration and show that it decomposes as a crossed product over the Hopf algebra of quasi-symmetric functions. We also describe the structure constants of the multiplication as a certain number of facets of the permutahedron. Our results reveal a close relationship between the structure of this Hopf algebra and the weak order on the symmetric groups.

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Marcelo Aguiar, Frank Sottile. 2002-03-27. Structure of the Malvenuto-Reutenauer Hopf algebra of permutations (Extended Abstract). https://arxiv.org/abs/math/0203101

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