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

Terms

a(0) =1a(1) =4a(2) =16a(3) =63a(4) =248a(5) =976a(6) =3841a(7) =15116a(8) =59488a(9) =234111a(10) =921328a(11) =3625824a(12) =14269185a(13) =56155412a(14) =220995824a(15) =869714111a(16) =3422701032a(17) =13469808304a(18) =53009519105a(19) =208615375388a(20) =820991693248