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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 70 |
| 5 | 526 |
| 6 | 13167 |
| 7 | 280772 |
| 8 | 20048886 |
| 9 | 1215446794 |
| 10 | 247358122583 |
| 11 | 42663813089328 |
| 12 | 24736951705389664 |
| 13 | 12142696908022734304 |
| 14 | 20054892679528741176540 |
| 15 | 28022410984084414473869168 |
[1,3,8,70,526,13167,280772,20048886,1215446794, 247358122583,42663813089328,24736951705389664, 12142696908022734304,20054892679528741176540, 28022410984084414473869168] |