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

Terms

a(0) =1a(1) =3a(2) =8a(3) =20a(4) =49a(5) =119a(6) =288a(7) =696a(8) =1681a(9) =4059a(10) =9800a(11) =23660a(12) =57121a(13) =137903a(14) =332928a(15) =803760a(16) =1940449a(17) =4684659a(18) =11309768a(19) =27304196a(20) =65918161a(21) =159140519a(22) =384199200a(23) =927538920a(24) =2239277041a(25) =5406093003a(26) =13051463048a(27) =31509019100a(28) =76069501249