1980
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1 1 --- 1 1 --- --- --- --- 1 --- 1 ---
2 --- --- 1 --- --- --- --- 1 --- 1,2 1 ---
3 --- --- --- --- --- 1 --- --- --- --- --- 1
4 1 1 1,2 --- --- --- --- --- 1 --- --- 1
5 1 --- --- --- --- 1 --- --- --- 1 --- 1
6 --- 1 --- --- 1 --- --- --- --- --- 1 ---
7 1 1 1 1 --- --- --- --- 1 1 1 1
8 1 1 --- 1 1 --- 1 1 1 --- 1 1
9 --- 1 --- 1 1 --- 1 --- --- --- --- 1
10 1 1 1,2 --- 1 --- --- 1 --- 1,2 --- 1
11 1 1 1 --- --- 1 --- --- --- --- 1 ---
12 --- 1,2 1 --- 1 1 --- --- --- --- 1 ---
13 1 --- 1 1 --- --- --- --- 1,2 1 --- 1
14 --- 1 1 --- --- --- --- --- --- 1 1 ---
15 --- 1,2 1 1,2 1,2 --- --- --- 1 --- --- 1
16 --- 1 --- 1 --- --- 1 --- 1 --- --- 1
17 --- --- --- --- 1 --- --- --- 1 1 --- 1
18 1 --- --- --- --- 1 --- 1 --- 1 1 ---
19 --- --- 1 --- 1 --- --- --- 1,2 --- 1 1
20 --- 1 1 --- 1 --- --- 1 --- --- --- 1
21 1 1 --- --- 1 --- --- --- 1 --- 1 1
22 1 1,2 1 1 --- --- 1 --- --- --- 1 1
23 --- --- 1 --- 1 1 --- --- 1 --- --- ---
24 1 1,2 --- 1 1 1 --- --- 1 --- --- 1
25 1 --- --- 1 --- --- --- --- 1 --- 1 ---
26 1 1 1 --- --- 1,2 --- 1 --- --- --- ---
27 --- 1,2 1 1 1 --- 1,2 1 1 --- 1 ---
28 1 --- 1 --- --- --- 1 --- 1 --- 1,2 ---
29 --- 1 --- 1 --- 1 1 --- 1 --- --- 1
30 ---   1 1 1,2 1 --- --- 1 --- 1 ---
31 ---   ---   1   --- ---   ---   ---