A123689 based sequence as SO(A123689(n)) dimensions.

Terms

a(0) =0a(1) =1a(2) =6a(3) =45a(4) =120a(5) =325a(6) =496a(7) =1035a(8) =1770a(9) =2701a(10) =3828a(11) =5778a(12) =7626a(13) =10585a(14) =14706a(15) =18721a(16) =23220a(17) =30628a(18) =37950a(19) =47278