Expansion of (eta(q^13) / eta(q))^2 in powers of q.

Terms

a(0) =1a(1) =2a(2) =5a(3) =10a(4) =20a(5) =36a(6) =65a(7) =110a(8) =185a(9) =300a(10) =481a(11) =752a(12) =1165a(13) =1768a(14) =2661a(15) =3946a(16) =5802a(17) =8430a(18) =12158a(19) =17360a(20) =24622a(21) =34632a(22) =48410a(23) =67188a(24) =92731a(25) =127182a(26) =173546a(27) =235508a(28) =318098a(29) =427536