G.f.: A(x) = Sum_{n>=0} x^n / Product_{k=1..n} (1-x^k)^k.

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =6a(5) =9a(6) =18a(7) =27a(8) =50a(9) =79a(10) =135a(11) =215a(12) =361a(13) =564a(14) =923a(15) =1450a(16) =2305a(17) =3590a(18) =5645a(19) =8693a(20) =13479a(21) =20611a(22) =31560a(23) =47880a(24) =72601a(25) =109195a(26) =164126a(27) =245109a(28) =365282a(29) =541642