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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 6 |
| 3 | 75 |
| 4 | 1565 |
| 5 | 48950 |
| 6 | 2145626 |
| 7 | 125727238 |
| 8 | 9507150815 |
| 9 | 902519025315 |
| 10 | 105203477607220 |
| 11 | 14786330708536422 |
| 12 | 2467862211341410635 |
| 13 | 482812610434512386665 |
| 14 | 109492763990117261581870 |
[1,1,6,75,1565,48950,2145626,125727238,9507150815, 902519025315,105203477607220,14786330708536422, 2467862211341410635,482812610434512386665, 109492763990117261581870] |