5 research outputs found
Combinatorics of -deformed stuffle Hopf algebras
In order to extend the Sch\"utzenberger's factorization to general
perturbations, the combinatorial aspects of the Hopf algebra of the
-deformed stuffle product is developed systematically in a parallel way
with those of the shuffle product
Structure of Polyzetas and Explicit Representation on Transcendence Bases of Shuffle and Stuffle Algebras
International audiencePolyzetas, indexed by words, satisfy shuffle and quasi-shuffle identities. In this respect, one can explore the multiplicative and algorithmic (locally finite) properties of their generating series. In this paper, we construct pairs of bases in duality on which polyzetas are established in order to compute local coordinates in the infinite dimensional Lie groups where their non-commutative generating series live. We also propose new algorithms leading to the ideal of polynomial relations, homogeneous in weight, among polyzetas (the graded kernel) and their explicit representation (as data structures) in terms of irreducible elements