A063691 without zeros.

Terms

a(0) =1a(1) =3a(2) =3a(3) =3a(4) =1a(5) =6a(6) =3a(7) =3a(8) =3a(9) =6a(10) =3a(11) =3a(12) =6a(13) =4a(14) =6a(15) =6a(16) =6a(17) =3a(18) =6a(19) =3a(20) =9a(21) =9a(22) =6a(23) =3a(24) =3a(25) =6a(26) =6a(27) =1a(28) =6a(29) =6