2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/66298We develop a purely set-theoretic formalism for binary trees and binary graphs. We define a category of binary automata, and display it as a fibred category over the category of binary graphs. We also relate the notion of binary graphs to transition systems, which arise in the theory of concurrent computing.19 pagesCombinatoricsDiscrete MathematicsCategory Theory05C05 (Primary) 18D30, 05C62, 18B20, 68Q85 (Secondary)text