1 One
11 (one one above)
21(one one is two ones)
1211 (one two, one one)
111221 (one one, one two, two ones)
3112211 (three ones, two twos, one one)
13212221 (one three, two ones, two twos, two ones)
111312113211 (one one, one three, one two, one one, three twos, one one)
Your turn ! You tell me when you find a 4...