Shifts 4 places left under Euler transform with a(0)=0 and a(n)=1 for n < 4.

Terms

a(0) =0a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =2a(7) =3a(8) =5a(9) =7a(10) =12a(11) =18a(12) =30a(13) =47a(14) =78a(15) =125a(16) =209a(17) =341a(18) =571a(19) =946a(20) =1592a(21) =2663a(22) =4503a(23) =7594a(24) =12898a(25) =21891a(26) =37334a(27) =63691a(28) =109039a(29) =186816