Coefficient expansion of: f(t,y)=((1 + y)/y - Exp[t/2])/(-1 + y*Exp[t]).

Terms

a(0) =1a(1) =1a(2) =3a(3) =2a(4) =3a(5) =7a(6) =17a(7) =17a(8) =7a(9) =15a(10) =116a(11) =122a(12) =116a(13) =15a(14) =31a(15) =627a(16) =1262a(17) =1262a(18) =627a(19) =31a(20) =63a(21) =2990a(22) =12433a(23) =15108a(24) =12433a(25) =2990a(26) =63a(27) =127a(28) =13309a(29) =107151