Expansion of 1 / ((1-x-x^2-x^3)*(1-x-x^3)).

Terms

a(0) =1a(1) =2a(2) =4a(3) =9a(4) =18a(5) =35a(6) =68a(7) =130a(8) =246a(9) =463a(10) =867a(11) =1617a(12) =3007a(13) =5579a(14) =10332a(15) =19107a(16) =35295a(17) =65140a(18) =120137a(19) =221444a(20) =407999a(21) =751453a(22) =1383641a(23) =2547116a(24) =4688106a(25) =8627504a(26) =15875390a(27) =29209560a(28) =53739655a(29) =98864470