The Hopf algebra of finite topologies and mould composition
arXiv:1503.03820
Abstract
We exhibit an internal coproduct on the Hopf algebra of finite topologies recently defined by the second author, C. Malvenuto and F. Patras, dual to the composition of "quasi-ormoulds", which are the natural version of J. Ecalle's moulds in this setting. All these results are displayed in the linear species formalism.
23 pages, one axodraw figure, Acknowledgements added