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

Terms

a(0) =1a(1) =1a(2) =2a(3) =2a(4) =5a(5) =5a(6) =15a(7) =15a(8) =34a(9) =46a(10) =84a(11) =96a(12) =246a(13) =282a(14) =512a(15) =696a(16) =1421a(17) =1713a(18) =3436a(19) =4084a(20) =8227a(21) =10821a(22) =19128a(23) =23258a(24) =48474a(25) =60943a(26) =106780a(27) =139313a(28) =252748a(29) =322577