G.f.: 1/Product_{k>=1} (1-prime(k)*x^prime(k)).

Terms

a(0) =1a(1) =0a(2) =2a(3) =3a(4) =4a(5) =11a(6) =17a(7) =29a(8) =49a(9) =85a(10) =144a(11) =226a(12) =404a(13) =603a(14) =1025a(15) =1679a(16) =2558a(17) =4201a(18) =6677a(19) =10190a(20) =16599a(21) =25681a(22) =39643a(23) =61830a(24) =96771a(25) =147114a(26) =228338a(27) =352725a(28) =533291a(29) =818624