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

Terms

a(0) =3a(1) =9a(2) =21a(3) =57a(4) =129a(5) =345a(6) =777a(7) =2073a(8) =4665a(9) =12441a(10) =27993a(11) =74649a(12) =167961a(13) =447897a(14) =1007769a(15) =2687385a(16) =6046617a(17) =16124313a(18) =36279705a(19) =96745881a(20) =217678233a(21) =580475289a(22) =1306069401a(23) =3482851737a(24) =7836416409a(25) =20897110425a(26) =47018498457