The sequence 12, 15, 18, 21, 51, 81, ... contains all positive multiples of 3 that contain at least one digit that is a 1. What is the 50th term of the sequence?
+476 There may be an easier way to do this, but I would just go through the multiples and find them.
12, 15, 18, 21, 51, 81, 102, 105, 108, 111
114, 117, 120, 123, 126, 129, 132, 135, 138, 141
144, 147, 150, 153, 156, 159, 162, 165, 168, 171
174, 177, 180, 183, 186, 189, 192, 195, 198, 201
210, 213, 216, 219, 231, 261, 291, 312, 315, 318.
