Numbers with digits 3 and 4 only.

Terms

a(0) =3a(1) =4a(2) =33a(3) =34a(4) =43a(5) =44a(6) =333a(7) =334a(8) =343a(9) =344a(10) =433a(11) =434a(12) =443a(13) =444a(14) =3333a(15) =3334a(16) =3343a(17) =3344a(18) =3433a(19) =3434a(20) =3443a(21) =3444a(22) =4333a(23) =4334a(24) =4343a(25) =4344a(26) =4433a(27) =4434a(28) =4443a(29) =4444