Expansion of g.f. x*(1-6*x^2)/(1-3*x-2*x^2+6*x^3).

Terms

a(0) =1a(1) =3a(2) =5a(3) =15a(4) =37a(5) =111a(6) =317a(7) =951a(8) =2821a(9) =8463a(10) =25325a(11) =75975a(12) =227797a(13) =683391a(14) =2049917a(15) =6149751a(16) =18448741a(17) =55346223a(18) =166037645a(19) =498112935a(20) =1494336757a(21) =4483010271a(22) =13449026717a(23) =40347080151a(24) =121041232261a(25) =363123696783