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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 14 |
| 6 | 52 |
| 7 | 228 |
| 8 | 1209 |
| 9 | 7463 |
| 10 | 52520 |
| 11 | 407856 |
| 12 | 3414672 |
| 13 | 30229061 |
| 14 | 279124327 |
[1,1,2,5,14,52,228,1209,7463,52520,407856,3414672, 30229061,279124327] |