Coefficients in the expansion Product_{ n>=1 } (1-q^(2n-1))^2/(1-q^(2n))^2.

Terms

a(0) =1a(1) =-2a(2) =3a(3) =-6a(4) =11a(5) =-18a(6) =28a(7) =-44a(8) =69a(9) =-104a(10) =152a(11) =-222a(12) =323a(13) =-460a(14) =645a(15) =-902a(16) =1254a(17) =-1722a(18) =2343a(19) =-3174a(20) =4278a(21) =-5722a(22) =7601a(23) =-10056a(24) =13250a(25) =-17358a(26) =22623a(27) =-29382a(28) =38021a(29) =-48984