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

Terms

a(0) =1a(1) =7a(2) =30a(3) =108a(4) =360a(5) =1152a(6) =3600a(7) =11088a(8) =33840a(9) =102672a(10) =310320a(11) =935568a(12) =2815920a(13) =8466192a(14) =25435440a(15) =76380048a(16) =229287600a(17) =688157712a(18) =2065062960a(19) =6196368528a(20) =18591464880a(21) =55779113232a(22) =167346776880a(23) =502059205008