Expansion of Sum_{k>0} x^(3*k)/(1+x^k)^4.

Terms

a(0) =0a(1) =0a(2) =1a(3) =-4a(4) =10a(5) =-19a(6) =35a(7) =-60a(8) =85a(9) =-110a(10) =165a(11) =-243a(12) =286a(13) =-329a(14) =466a(15) =-620a(16) =680a(17) =-751a(18) =969a(19) =-1254a(20) =1366a(21) =-1375a(22) =1771a(23) =-2323a(24) =2310a(25) =-2314a(26) =3010a(27) =-3609a(28) =3654a(29) =-3734