Least k such that decimal representation of k*n contains only digits 0 and 9.

Terms

a(0) =9a(1) =45a(2) =3a(3) =225a(4) =18a(5) =15a(6) =1287a(7) =1125a(8) =1a(9) =9a(10) =9a(11) =75a(12) =693a(13) =6435a(14) =6a(15) =5625a(16) =5877a(17) =5a(18) =5211a(19) =45a(20) =429a(21) =45a(22) =43083a(23) =375a(24) =36a(25) =3465a(26) =37a(27) =32175a(28) =341721a(29) =3