Expansion of g.f.: (1 + x - 2*x^2 + 2*x^4)/((1-x)*(1-3*x^2)).

Terms

a(0) =1a(1) =2a(2) =3a(3) =6a(4) =11a(5) =20a(6) =35a(7) =62a(8) =107a(9) =188a(10) =323a(11) =566a(12) =971a(13) =1700a(14) =2915a(15) =5102a(16) =8747a(17) =15308a(18) =26243a(19) =45926a(20) =78731a(21) =137780a(22) =236195a(23) =413342a(24) =708587a(25) =1240028a(26) =2125763a(27) =3720086a(28) =6377291a(29) =11160260