Expansion of (1-3*x)/(1-5*x).

Terms

a(0) =1a(1) =2a(2) =10a(3) =50a(4) =250a(5) =1250a(6) =6250a(7) =31250a(8) =156250a(9) =781250a(10) =3906250a(11) =19531250a(12) =97656250a(13) =488281250a(14) =2441406250a(15) =12207031250a(16) =61035156250a(17) =305175781250