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

Terms

a(0) =1a(1) =0a(2) =4a(3) =4a(4) =24a(5) =56a(6) =188a(7) =540a(8) =1648a(9) =4912a(10) =14772a(11) =44276a(12) =132872a(13) =398568a(14) =1195756a(15) =3587212a(16) =10761696a(17) =32285024a(18) =96855140a(19) =290565348a(20) =871696120a(21) =2615088280a(22) =7845264924a(23) =23535794684a(24) =70607384144a(25) =211822152336a(26) =635466457108