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

Terms

a(0) =2a(1) =3a(2) =15a(3) =54a(4) =207a(5) =783a(6) =2970a(7) =11259a(8) =42687a(9) =161838a(10) =613575a(11) =2326239a(12) =8819442a(13) =33437043a(14) =126769455a(15) =480619494a(16) =1822166847a(17) =6908359023a(18) =26191577610a(19) =99299809899a(20) =376474162527