Expansion of (1-x)*(1-2x)*(1-3x)/((1-5x+5*x^2)*(1-3x+x^2)).

Terms

a(0) =1a(1) =2a(2) =6a(3) =20a(4) =69a(5) =242a(6) =857a(7) =3054a(8) =10930a(9) =39236a(10) =141153a(11) =508598a(12) =1834641a(13) =6623450a(14) =23926334a(15) =86468052a(16) =312587197a(17) =1130277914a(18) =4087621545a(19) =14784539846a(20) =53478888618a(21) =193456813508a(22) =699850536281