Multiples of 3 using only prime digits (2, 3, 5 and 7).

Terms

a(0) =3a(1) =27a(2) =33a(3) =57a(4) =72a(5) =75a(6) =222a(7) =225a(8) =237a(9) =252a(10) =255a(11) =273a(12) =327a(13) =333a(14) =357a(15) =372a(16) =375a(17) =522a(18) =525a(19) =537a(20) =552a(21) =555a(22) =573a(23) =723a(24) =732a(25) =735a(26) =753a(27) =777a(28) =2223a(29) =2232