Expansion of (phi(q) / phi(q^3) - 1) / 2 in powers of q where phi() is a Ramanujan theta function.

Terms

a(0) =1a(1) =0a(2) =-1a(3) =-1a(4) =0a(5) =2a(6) =2a(7) =0a(8) =-3a(9) =-4a(10) =0a(11) =5a(12) =6a(13) =0a(14) =-8a(15) =-9a(16) =0a(17) =12a(18) =14a(19) =0a(20) =-18a(21) =-20a(22) =0a(23) =26a(24) =29a(25) =0a(26) =-37a(27) =-42a(28) =0a(29) =52