Numbers whose base-3 and base-7 expansions have no digits in common.

Terms

a(0) =3a(1) =4a(2) =5a(3) =6a(4) =8a(5) =24a(6) =25a(7) =26a(8) =27a(9) =30a(10) =31a(11) =32a(12) =33a(13) =34a(14) =37a(15) =38a(16) =39a(17) =40a(18) =41a(19) =45a(20) =46a(21) =47a(22) =48a(23) =60a(24) =62a(25) =74a(26) =78a(27) =80a(28) =117a(29) =118