Expansion of g.f. x*(1+x)^5/(1-x)^7.

Terms

a(0) =0a(1) =1a(2) =12a(3) =73a(4) =304a(5) =985a(6) =2668a(7) =6321a(8) =13504a(9) =26577a(10) =48940a(11) =85305a(12) =142000a(13) =227305a(14) =351820a(15) =528865a(16) =774912a(17) =1110049a(18) =1558476a(19) =2149033a(20) =2915760a(21) =3898489a(22) =5143468a(23) =6704017a(24) =8641216a(25) =11024625a(26) =13933036a(27) =17455257a(28) =21690928a(29) =26751369