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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 15 |
| 4 | 121 |
| 5 | 3906 |
| 6 | 299593 |
| 7 | 67977560 |
| 8 | 39714002329 |
| 9 | 62556901638175 |
| 10 | 257985813269495081 |
| 11 | 2806709131423433412540 |
| 12 | 80052769211806164721787281 |
| 13 | 5990939163682951316587217125254 |
| 14 | 1174714712853607653027182667701045767 |
| 15 | 603476089599958368340121395090311986863711 |
[1,2,3,15,121,3906,299593,67977560,39714002329, 62556901638175,257985813269495081, 2806709131423433412540,80052769211806164721787281, 5990939163682951316587217125254, 1174714712853607653027182667701045767, 603476089599958368340121395090311986863711] |