Coefficient of x^n in the expansion of (1+x^4+x^5)^n.

Terms

a(0) =1a(1) =0a(2) =0a(3) =0a(4) =4a(5) =5a(6) =0a(7) =0a(8) =28a(9) =72a(10) =45a(11) =0a(12) =220a(13) =858a(14) =1092a(15) =455a(16) =1820a(17) =9520a(18) =18360a(19) =15504a(20) =20349a(21) =101745a(22) =263340a(23) =336490a(24) =347116a(25) =1115730a(26) =3453450a(27) =5920200a(28) =6835140a(29) =13775580