Least k such that decimal representation of k*n contains only digits 0 and 3.

Terms

a(0) =3a(1) =15a(2) =1a(3) =75a(4) =6a(5) =5a(6) =429a(7) =375a(8) =37a(9) =3a(10) =3a(11) =25a(12) =231a(13) =2145a(14) =2a(15) =1875a(16) =1959a(17) =185a(18) =1737a(19) =15a(20) =143a(21) =15a(22) =14361a(23) =125a(24) =12a(25) =1155a(26) =12345679a(27) =10725a(28) =113907a(29) =1