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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 16 |
| 6 | 61 |
| 7 | 272 |
| 8 | 1385 |
| 9 | 7936 |
| 10 | 50521 |
| 11 | 353792 |
| 12 | 2702765 |
| 13 | 22368256 |
| 14 | 199360981 |
| 15 | 1903757312 |
| 16 | 19391512145 |
| 17 | 209865342976 |
| 18 | 2404879675441 |
| 19 | 29088885112832 |
| 20 | 370371188237525 |
| 21 | 4951498053124096 |
| 22 | 69348874393137901 |
| 23 | 1015423886506852352 |
| 24 | 15514534163557086905 |
| 25 | 246921480190207983616 |
| 26 | 4087072509293123892361 |
[1,1,1,2,5,16,61,272,1385,7936,50521,353792, 2702765,22368256,199360981,1903757312,19391512145, 209865342976,2404879675441,29088885112832, 370371188237525,4951498053124096, 69348874393137901,1015423886506852352, 15514534163557086905,246921480190207983616, 4087072509293123892361] |