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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 105 |
| 5 | 651 |
| 6 | 1953 |
| 7 | 35433 |
| 8 | 3011805 |
| 9 | 513010785 |
| 10 | 376207909 |
| 11 | 70008871793 |
| 12 | 40955189998905 |
| 13 | 25804920098540835 |
| 14 | 158515937748179415 |
| 15 | 33510269239965128331 |
| 16 | 43060695973355189905335 |
| 17 | 332000498936684593887186105 |
| 18 | 2703432634198717407367086855 |
[1,1,3,7,105,651,1953,35433,3011805,513010785, 376207909,70008871793,40955189998905, 25804920098540835,158515937748179415, 33510269239965128331,43060695973355189905335, 332000498936684593887186105, 2703432634198717407367086855] |