a(n) is the number of divisors of n^n - n.

Terms

a(0) =2a(1) =8a(2) =18a(3) =40a(4) =24a(5) =120a(6) =48a(7) =336a(8) =80a(9) =192a(10) =72a(11) =1920a(12) =48a(13) =288a(14) =23040a(15) =1728a(16) =36a(17) =10240a(18) =72a(19) =7680a(20) =432a(21) =240a(22) =384a(23) =32256a(24) =640a(25) =49152a(26) =2016a(27) =3840a(28) =96a(29) =193536