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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 22 |
| 4 | 200 |
| 5 | 2921 |
| 6 | 67529 |
| 7 | 2502327 |
| 8 | 149148042 |
| 9 | 14187953164 |
| 10 | 2166282171177 |
| 11 | 529836175417335 |
| 12 | 207601280437878258 |
| 13 | 130373625773755053650 |
[1,4,22,200,2921,67529,2502327,149148042, 14187953164,2166282171177,529836175417335, 207601280437878258,130373625773755053650] |