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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 2 |
| 3 | 10 |
| 4 | 7 |
| 5 | 63 |
| 6 | 38 |
| 7 | 1252 |
| 8 | 456 |
| 9 | 42951 |
| 10 | 11051 |
| 11 | 2411116 |
| 12 | 461788 |
| 13 | 300699154 |
| 14 | 38535499 |
| 15 | 76231743090 |
| 16 | 6586274655 |
| 17 | 36545866507976 |
| 18 | 2160036716063 |
| 19 | 34857588279065543 |
| 20 | 1397443585027894 |
| 21 | 67527452467684091249 |
[1,2,2,10,7,63,38,1252,456,42951,11051,2411116, 461788,300699154,38535499,76231743090,6586274655, 36545866507976,2160036716063,34857588279065543, 1397443585027894,67527452467684091249] |