Expansion of Product_{m>=1} (1-m*q^m)^-4.

Terms

a(0) =1a(1) =4a(2) =18a(3) =64a(4) =219a(5) =676a(6) =2030a(7) =5736a(8) =15793a(9) =41864a(10) =108430a(11) =273240a(12) =675526a(13) =1634780a(14) =3891960a(15) =9108872a(16) =21018870a(17) =47815572a(18) =107446898a(19) =238524144a(20) =523812125a(21) =1138233100a(22) =2449710880a(23) =5223395480a(24) =11042278208