G.f.: Sum_{k>=1} x^k/(1-x^k) * Product_{k>=1} 1/(1-x^k)^2.

Terms

a(0) =0a(1) =1a(2) =4a(3) =11a(4) =27a(5) =58a(6) =119a(7) =227a(8) =420a(9) =744a(10) =1287a(11) =2160a(12) =3561a(13) =5739a(14) =9113a(15) =14224a(16) =21924a(17) =33327a(18) =50126a(19) =74531a(20) =109802a(21) =160211a(22) =231875a(23) =332821a(24) =474313a(25) =671072a(26) =943411a(27) =1317826a(28) =1830290a(29) =2527583