# distance  frequency
1  6663
2  84150
3  1012260
4  8940241
5  41805394
6  88716757
7  90934524
8  53290886
9  21718921
10  7364864
11  2280445
12  669582
13  188004
14  50232
15  12433
16  2897
17  572
18  161
19  14