G.f.: A(x) = Sum_{n>=0} x^n * Product_{d|n} (1 + x^d)^(n/d).

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =6a(5) =10a(6) =17a(7) =32a(8) =54a(9) =92a(10) =170a(11) =311a(12) =555a(13) =986a(14) =1756a(15) =3100a(16) =5370a(17) =9295a(18) =16552a(19) =30535a(20) =57564a(21) =108830a(22) =202947a(23) =369829a(24) =659380a(25) =1162254a(26) =2053619a(27) =3675529a(28) =6683060a(29) =12293599