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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 51 |
| 5 | 201 |
| 6 | 834 |
| 7 | 3529 |
| 8 | 15075 |
| 9 | 65431 |
| 10 | 288278 |
| 11 | 1285263 |
| 12 | 5799470 |
| 13 | 26492103 |
| 14 | 122432628 |
| 15 | 572291385 |
| 16 | 2705760291 |
| 17 | 12937116213 |
| 18 | 62542367166 |
| 19 | 305668511259 |
| 20 | 1510080076410 |
| 21 | 7539381024297 |
| 22 | 38034307340076 |
| 23 | 193835252945487 |
| 24 | 997724306958606 |
| 25 | 5185731234177001 |
[1,1,3,13,51,201,834,3529,15075,65431,288278, 1285263,5799470,26492103,122432628,572291385, 2705760291,12937116213,62542367166,305668511259, 1510080076410,7539381024297,38034307340076, 193835252945487,997724306958606,5185731234177001] |