Families of Hopf algebras of trees and pre-Lie algebras

Pepijn van der Laan and Ieke Moerdijk

We study Hopf algebra structures on polynomial algebras generated by coloured trees. In particular, we establish the existence of a 2n-parameter family of such structures for trees coloured by n colours.

Homology, Homotopy and Applications, Vol. 8 (2006), No. 1, pp.243-256.

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