Expansion of (1-4*x)/(1-4*x-4*x^2).

Terms

a(0) =1a(1) =0a(2) =4a(3) =16a(4) =80a(5) =384a(6) =1856a(7) =8960a(8) =43264a(9) =208896a(10) =1008640a(11) =4870144a(12) =23515136a(13) =113541120a(14) =548225024a(15) =2647064576a(16) =12781158400a(17) =61712891904a(18) =297976201216