1 2
2 9
3 49
4 272
5 1509
6 8375
7 46586
8 259927
9 1454873
10 8167578
11 45975525
12 259412481
13 1466771294
14 8308711329
15 47142516717
16 267868554552
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18 8681096155047
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22 9227766021583954