Expansion of (1-x+7x^2)/((1-x)(1-2x)).

Terms

a(0) =1a(1) =2a(2) =11a(3) =29a(4) =65a(5) =137a(6) =281a(7) =569a(8) =1145a(9) =2297a(10) =4601a(11) =9209a(12) =18425a(13) =36857a(14) =73721a(15) =147449a(16) =294905a(17) =589817a(18) =1179641a(19) =2359289a(20) =4718585a(21) =9437177a(22) =18874361a(23) =37748729a(24) =75497465a(25) =150994937a(26) =301989881a(27) =603979769a(28) =1207959545a(29) =2415919097