Expansion of Product_{m>=1} (1+m*q^m)^-20.

Terms

a(0) =1a(1) =-20a(2) =170a(3) =-800a(4) =2415a(5) =-6404a(6) =21550a(7) =-71080a(8) =178295a(9) =-419200a(10) =1203282a(11) =-3294360a(12) =7476320a(13) =-17381780a(14) =44919500a(15) =-107605880a(16) =237628435a(17) =-544086720a(18) =1273805460a(19) =-2864694880a(20) =6256648862a(21) =-13710129840