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arXiv · 1406.1616

m-dendriform algebras

Jean-Christophe Novelli
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Abstract

The Fuss-Catalan numbers are a generalization of the Catalan numbers. They enumerate a large class of objects and in particular m-Dyck paths and m+1-ary trees. Recently, F. Bergeron defined an analogue for generic m of the Tamari order on classical Dyck words. The author and J.-Y. Thibon showed that the combinatorial Hopf algebras related to these m-Tamari orders are defined thanks to the same monoid, the sylvester monoid, as in the m=1 case and that all related Hopf algebras also have m analogues. We present here the m-generalization of another construction on Catalan sets: the dendriform algebras. These algebras are presented in two different ways: first by relations between the m+1 operations, relations that are very similar to the classical relations; and then by explicit operations splitting the classical dendriform operations defined on words into new operations. We then investigate their dual and show they are Koszul.

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Jean-Christophe Novelli. 2014-06-06. m-dendriform algebras. https://arxiv.org/abs/1406.1616

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