Expansion of (1-4x^2)/(1+4x+3x^2).

Terms

a(0) =1a(1) =-4a(2) =9a(3) =-24a(4) =69a(5) =-204a(6) =609a(7) =-1824a(8) =5469a(9) =-16404a(10) =49209a(11) =-147624a(12) =442869a(13) =-1328604a(14) =3985809a(15) =-11957424a(16) =35872269a(17) =-107616804a(18) =322850409a(19) =-968551224a(20) =2905653669a(21) =-8716961004a(22) =26150883009a(23) =-78452649024a(24) =235357947069a(25) =-706073841204