Expansion of (1-9x-27x^3)^(-1/3).

Terms

a(0) =1a(1) =3a(2) =18a(3) =135a(4) =1053a(5) =8505a(6) =70470a(7) =594135a(8) =5073840a(9) =43761870a(10) =380433024a(11) =3328474032a(12) =29276671347a(13) =258669163665