中央研究院 数學研咒所 Motzkin paths An n-Motizkin path is a lattice path from(, 0 to(n, O)in the first quadrant consisting of up step(1, 1), level-step(1, 0)and down-step(1, -1) Motzkin number:1,1,2,4,9,21,51,127,323,835,…, 第5页第5页 Motzkin paths • An n-Motizkin path is a lattice path from (0,0) to (n,0) in the first quadrant consisting of up￾step (1,1), level-step (1,0) and down-step (1,-1). Motzkin number:1, 1, 2, 4, 9, 21, 51, 127, 323, 835, …