Expansion of 1/(1-4*x-x^3).

Terms

a(0) =1a(1) =4a(2) =16a(3) =65a(4) =264a(5) =1072a(6) =4353a(7) =17676a(8) =71776a(9) =291457a(10) =1183504a(11) =4805792a(12) =19514625a(13) =79242004a(14) =321773808a(15) =1306609857a(16) =5305681432a(17) =21544499536a(18) =87484608001a(19) =355244113436