Expansion of (phi(-q^3) / phi(-q))^2 in powers of q where phi is a Ramanujan theta function.

Terms

a(0) =1a(1) =4a(2) =12a(3) =28a(4) =60a(5) =120a(6) =228a(7) =416a(8) =732a(9) =1252a(10) =2088a(11) =3408a(12) =5460a(13) =8600a(14) =13344a(15) =20424a(16) =30876a(17) =46152a(18) =68268a(19) =100016a(20) =145224a(21) =209120a(22) =298800a(23) =423840a(24) =597108a(25) =835804a(26) =1162824a(27) =1608508a(28) =2212896a(29) =3028632