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

Terms

a(0) =1a(1) =3a(2) =9a(3) =25a(4) =67a(5) =175a(6) =449a(7) =1137a(8) =2851a(9) =7095a(10) =17553a(11) =43225a(12) =106051a(13) =259423a(14) =633089a(15) =1541985a(16) =3749827a(17) =9107175a(18) =22095249a(19) =53559817a(20) =129739171a(21) =314086735a(22) =760009793a(23) =1838300625a(24) =4444999651a(25) =10745077143a(26) =25968708369a(27) =62749602745