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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 43 |
| 6 | 147 |
| 7 | 578 |
| 8 | 2702 |
| 9 | 15252 |
| 10 | 103150 |
| 11 | 817928 |
| 12 | 7428844 |
| 13 | 75807522 |
| 14 | 856512850 |
| 15 | 10596715538 |
[1,1,2,5,14,43,147,578,2702,15252,103150,817928, 7428844,75807522,856512850,10596715538] |