Article

The primitives of the Hopf algebra of noncommutative symmetric functions

11/2004; DOI: 10.11606/issn.2316-9028.v1i2p175-202
Source: arXiv

ABSTRACT Let NSymm be the Hopf algebra of noncommutative symmetric functions over the integers. In this paper a description is given of its Lie algebra of primitives over the integers, Prim(NSymm), in terms of recursion formulas. For each of the primitives of a basis of Prim(NSymm), indexed by Lyndon words, there is a recursively given divided power series over it. This gives another proof of the theorem that the algebra of quasi-symmetric functions is free over the integers.

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Available from: Michiel Hazewinkel, Apr 28, 2015
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