Series expansion of (eta(q^9) / eta(q))^3 in powers of q.

Terms

a(0) =1a(1) =3a(2) =9a(3) =22a(4) =51a(5) =108a(6) =221a(7) =429a(8) =810a(9) =1476a(10) =2631a(11) =4572a(12) =7802a(13) =13056a(14) =21519a(15) =34918a(16) =55935a(17) =88452a(18) =138332a(19) =213990a(20) =327852a(21) =497592a(22) =748833a(23) =1117692a(24) =1655719a(25) =2434938a(26) =3556791a(27) =5161808a(28) =7445631a(29) =10677096