Expansion of (1+27x^2-54x^3)/((1+3x)^2*(1-3x+9 x^2)).

Terms

a(0) =1a(1) =-3a(2) =36a(3) =-189a(4) =567a(5) =-2430a(6) =9477a(7) =-28431a(8) =104976a(9) =-373977a(10) =1121931a(11) =-3897234a(12) =13286025a(13) =-39858075a(14) =133923132a(15) =-444816117a(16) =1334448351a(17) =-4390765542a(18) =14334558093a(19) =-43003674279a(20) =139471376040a(21) =-449795187729