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

Terms

a(0) =0a(1) =1a(2) =5a(3) =10a(4) =18a(5) =27a(6) =39a(7) =52a(8) =68a(9) =85a(10) =105a(11) =126a(12) =150a(13) =175a(14) =203a(15) =232a(16) =264a(17) =297a(18) =333a(19) =370a(20) =410a(21) =451a(22) =495a(23) =540a(24) =588a(25) =637a(26) =689a(27) =742a(28) =798a(29) =855