Expansion of (1-x)^2/(1-5*x).

Terms

a(0) =1a(1) =3a(2) =16a(3) =80a(4) =400a(5) =2000a(6) =10000a(7) =50000a(8) =250000a(9) =1250000a(10) =6250000a(11) =31250000a(12) =156250000a(13) =781250000a(14) =3906250000a(15) =19531250000a(16) =97656250000a(17) =488281250000