Number of Motzkin n-paths with two kinds of level steps one of which is a final step.

Terms

a(0) =1a(1) =2a(2) =3a(3) =7a(4) =17a(5) =43a(6) =114a(7) =310a(8) =861a(9) =2433a(10) =6970a(11) =20198a(12) =59101a(13) =174373a(14) =518179a(15) =1549545a(16) =4659399a(17) =14079553a(18) =42732230a(19) =130208246a(20) =398174723a(21) =1221573603a(22) =3758835953a(23) =11597578995a(24) =35872937745a(25) =111216324015a(26) =345539568900