Expansion of Product_{k>=1} (1 + x^(2*k))^(2*k)/(1 + x^(2*k-1))^(2*k-1).

Terms

a(0) =1a(1) =-1a(2) =3a(3) =-6a(4) =11a(5) =-22a(6) =42a(7) =-74a(8) =131a(9) =-231a(10) =395a(11) =-669a(12) =1122a(13) =-1851a(14) =3029a(15) =-4915a(16) =7891a(17) =-12572a(18) =19881a(19) =-31203a(20) =48657a(21) =-75391a(22) =116096a(23) =-177792a(24) =270822a(25) =-410394a(26) =618905a(27) =-929052a(28) =1388403a(29) =-2066140