a(n) = Sum_{d|n} d^d * binomial(n/d,d).

Terms

a(0) =1a(1) =2a(2) =3a(3) =8a(4) =5a(5) =18a(6) =7a(7) =32a(8) =36a(9) =50a(10) =11a(11) =180a(12) =13a(13) =98a(14) =285a(15) =384a(16) =17a(17) =702a(18) =19a(19) =1480a(20) =966a(21) =242a(22) =23a(23) =5640a(24) =3150a(25) =338a(26) =2295a(27) =9352a(28) =29a(29) =22440