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

Terms

a(0) =1a(1) =2a(2) =6a(3) =18a(4) =52a(5) =152a(6) =444a(7) =1296a(8) =3784a(9) =11048a(10) =32256a(11) =94176a(12) =274960a(13) =802784a(14) =2343840a(15) =6843168a(16) =19979584a(17) =58333184a(18) =170311872a(19) =497249280a(20) =1451788672a(21) =4238699648a(22) =12375475200a(23) =36131927040a(24) =105492203776a(25) =307999212032a(26) =899246685696