Smallest k for which k, 2k, ... n*k all contain the digit 2.

Terms

a(0) =2a(1) =12a(2) =124a(3) =624a(4) =624a(5) =642a(6) =4062a(7) =4062a(8) =4128a(9) =4128a(10) =23041a(11) =23041a(12) =23041a(13) =23041a(14) =144032a(15) =144032a(16) =144032a(17) =144032a(18) =144032a(19) =144032a(20) =144032a(21) =1201804a(22) =1201804a(23) =1201804a(24) =1276048a(25) =1276048a(26) =1276048a(27) =1276048a(28) =1276048a(29) =1276048