a(n) = sum_(d|n) product_(d_x|n, d_x<=d) d_x.

Terms

a(0) =1a(1) =3a(2) =4a(3) =11a(4) =6a(5) =45a(6) =8a(7) =75a(8) =31a(9) =113a(10) =12a(11) =1905a(12) =14a(13) =213a(14) =244a(15) =1099a(16) =18a(17) =6201a(18) =20a(19) =8451a(20) =466a(21) =509a(22) =24a(23) =346929a(24) =131a(25) =705a(26) =760a(27) =22803a(28) =30a(29) =839019