On Generating Functions of Generating Trees
Résumé
Generating trees describe conveniently certain families of combinatorial objects: each node of the tree corresponds to an object, and the branch leading to the node encodes the choices made in the construction of the object. Generating trees lead to a fast computation of enumeration sequences (sometimes, to explicit formulae as well) while providing efficient random generation algorithms. In this paper, we investigate the relationship between structural properties of the rules defining such trees and the rationality, algebraicity, or transcendence of the corresponding generating functions.