A comodule-bialgebra structure for word-series substitution and mould composition
Keywords: 16T05; 16T10; 16T15; 16T30; Arborification; Bialgebra; B- and S-series; Comodule-Hopf algebra; Hopf algebra; Mould calculus; Quasi-shuffle product; Rooted trees; Surjections; Weak quasi-shuffle; Word series;