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arXiv · 0901.2202

The infinitesimal Hopf algebra and the operads of planar forests

Loïc Foissy
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Abstract

We introduce two operads which own the set of planar forests as a basis. With its usual product and two other products defined by different types of graftings, the algebra of planar rooted trees H becomes an algebra over these operads. The compatibility with the infinitesimal coproduct of H and these structures is studied. As an application, an inductive way of computing the dual basis of H for its infinitesimal pairing is given. Moreover, three Cartier-Quillen-Milnor-Moore theorems are given for the operads of planar forests and a rigidity theorem for one of them.

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Loïc Foissy. 2009-01-15. The infinitesimal Hopf algebra and the operads of planar forests. https://arxiv.org/abs/0901.2202

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