Agradecimentos: The authors thank the Referee for his/her valuable comments and suggestions. The second author thanks Mustapha Rachidi for his valuable suggestions and comments. The authors express their sincere thanks to the INMA and Universidade Federal de Mato Grosso do Sul – UFMS/MEC – Brazil for their valuable support Ver menos

Abstract: This work presents a combinatorial bijection between the set of lattice paths and the set of ordered trees, both counted by the central coefficients of the expansion of the trinomial (1+ x + x ^2)^ n . Moreover, using a combinatorial interpretation of Catalan numbers, we establish a new set of ordered trees counted by a new sequence Ver menos