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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 19 |
| 3 | 65 |
| 4 | 216 |
| 5 | 715 |
| 6 | 2369 |
| 7 | 7855 |
| 8 | 26051 |
| 9 | 86400 |
| 10 | 286549 |
| 11 | 950345 |
| 12 | 3151831 |
| 13 | 10453085 |
| 14 | 34667784 |
| 15 | 114976135 |
| 16 | 381319781 |
| 17 | 1264651795 |
| 18 | 4194233399 |
| 19 | 13910227200 |
| 20 | 46133441401 |
| 21 | 153002131805 |
| 22 | 507433471819 |
| 23 | 1682909416265 |
| 24 | 5581389996216 |
[1,5,19,65,216,715,2369,7855,26051,86400,286549, 950345,3151831,10453085,34667784,114976135, 381319781,1264651795,4194233399,13910227200, 46133441401,153002131805,507433471819, 1682909416265,5581389996216] |