MacMahon's generalized sum of divisors function.

Terms

a(0) =1a(1) =3a(2) =9a(3) =15a(4) =30a(5) =45a(6) =67a(7) =99a(8) =135a(9) =175a(10) =231a(11) =306a(12) =354a(13) =465a(14) =540a(15) =681a(16) =765a(17) =945a(18) =1040a(19) =1305a(20) =1386a(21) =1695a(22) =1779a(23) =2205a(24) =2290a(25) =2754a(26) =2835a(27) =3438a(28) =3480a(29) =4185