2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/101065We present a simple combinatorial model for the characters of the irreducible integrable highest weight modules for complex symmetrizable Kac-Moody algebras. This model can be viewed as a discrete counterpart to the Littelmann path model. We describe crystal graphs and give a Littlewood-Richardson rule for decomposing tensor products of irreducible representations. The new model is based on the notion of a lambda-chain, which is a chain of positive roots defined by certain interlacing conditions.28 pages, 2 figuresRepresentation TheoryCombinatorics17B67; 22E46, 20G42text