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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 24 |
| 5 | 133 |
| 6 | 846 |
| 7 | 5661 |
| 8 | 39556 |
| 9 | 286000 |
| 10 | 2123329 |
| 11 | 16112057 |
| 12 | 124512556 |
| 13 | 977227830 |
| 14 | 7772368380 |
| 15 | 62535450861 |
| 16 | 508271324688 |
| 17 | 4168218286276 |
| 18 | 34455941596060 |
| 19 | 286864341314320 |
| 20 | 2403705165816240 |
| 21 | 20258850167232165 |
| 22 | 171652324167433710 |
| 23 | 1461462393790971585 |
| 24 | 12498416291503945764 |
[1,1,1,5,24,133,846,5661,39556,286000,2123329, 16112057,124512556,977227830,7772368380, 62535450861,508271324688,4168218286276, 34455941596060,286864341314320,2403705165816240, 20258850167232165,171652324167433710, 1461462393790971585,12498416291503945764] |