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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 24 |
| 4 | 205 |
| 5 | 1724 |
| 6 | 16968 |
| 7 | 172610 |
| 8 | 1830872 |
| 9 | 19860306 |
| 10 | 219630346 |
| 11 | 2464760150 |
| 12 | 28002352120 |
[1,7,24,205,1724,16968,172610,1830872,19860306, 219630346,2464760150,28002352120] |