Generate how many keys?
 9 18 31 37 40 + 4 5
 7 15 21 28 36 + 7 9
 5 15 21 37 42 + 7 9
 8 10 13 23 31 + 3 9
 1 10 12 20 43 + 2 4
10 17 18 23 36 + 1 2
16 21 28 33 49 + 3 6
15 21 25 27 44 + 1 8
 7 12 13 15 32 + 1 3
11 18 21 43 49 + 3 8