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

Terms

a(0) =1a(1) =1a(2) =2a(3) =2a(4) =4a(5) =4a(6) =8a(7) =8a(8) =14a(9) =15a(10) =24a(11) =25a(12) =43a(13) =45a(14) =69a(15) =74a(16) =113a(17) =120a(18) =187a(19) =198a(20) =291a(21) =314a(22) =452a(23) =483a(24) =720a(25) =770a(26) =1089a(27) =1182a(28) =1657a(29) =1784