1 0.500000
2 0.250000
3 0.750000
4 0.125000
5 0.625000
6 0.375000
7 0.875000
8 0.062500
9 0.562500
10 0.312500
11 0.812500
12 0.187500
13 0.687500
14 0.437500
15 0.937500
16 0.031250
17 0.531250
18 0.281250
19 0.781250
20 0.156250