2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/108963Riordan paths are Motzkin paths without horizontal steps on the x-axis. We establish a correspondence between Riordan paths and $(321,3\bar{1}42)$-avoiding derangements. We also present a combinatorial proof of a recurrence relation for the Riordan numbers in the spirit of the Foata-Zeilberger proof of a recurrence relation on the Schröder numbers.9 pages, 2 figuresCombinatorics05A15, 05A19text