Triangle read by rows: T(n,k) is the number of ordered trees with n edges and k branches.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =2a(6) =1a(7) =3a(8) =6a(9) =4a(10) =1a(11) =4a(12) =12a(13) =16a(14) =9a(15) =1a(16) =5a(17) =20a(18) =40a(19) =45a(20) =21a(21) =1a(22) =6a(23) =30a(24) =80a(25) =135a(26) =126a(27) =51a(28) =1a(29) =7