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

Terms

a(0) =1a(1) =1a(2) =4a(3) =1a(4) =6a(5) =10a(6) =8a(7) =1a(8) =37a(9) =26a(10) =12a(11) =82a(12) =14a(13) =50a(14) =384a(15) =1a(16) =18a(17) =811a(18) =20a(19) =626a(20) =2552a(21) =122a(22) =24a(23) =6562a(24) =3151a(25) =170a(26) =20440a(27) =2402a(28) =30a(29) =74900