a(n) = Product_{d|n} T(d) where T(x) = x*(x+1)/2 = A000217(x) = x-th triangular number.

Terms

a(0) =1a(1) =3a(2) =6a(3) =30a(4) =15a(5) =378a(6) =28a(7) =1080a(8) =270a(9) =2475a(10) =66a(11) =294840a(12) =91a(13) =8820a(14) =10800a(15) =146880a(16) =153a(17) =2908710a(18) =190a(19) =5197500a(20) =38808a(21) =50094a(22) =276a(23) =3184272000a(24) =4875a(25) =95823a(26) =102060a(27) =35809200a(28) =435a(29) =17401230000