Coefficient of x^n in the expansion of (1+x^3+x^4)^n.

Terms

a(0) =1a(1) =0a(2) =0a(3) =3a(4) =4a(5) =0a(6) =15a(7) =42a(8) =28a(9) =84a(10) =360a(11) =495a(12) =715a(13) =2860a(14) =6006a(15) =8463a(16) =23660a(17) =61880a(18) =104244a(19) =220932a(20) =596904a(21) =1201560a(22) =2313003a(23) =5753979a(24) =12983707a(25) =25477100a(26) =57557500a(27) =135227235a(28) =280913490a(29) =600900300