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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 25 |
| 4 | 42 |
| 5 | 133 |
| 6 | 618 |
| 7 | 643 |
| 8 | 701 |
| 9 | 1962 |
| 10 | 8150 |
| 11 | 147458 |
| 12 | 168459 |
| 13 | 356038 |
| 14 | 415870 |
| 15 | 536685 |
| 16 | 637757 |
| 17 | 1093612 |
| 18 | 1207618 |
| 19 | 3368325 |
| 20 | 3470706 |
| 21 | 23400631 |
| 22 | 37621653 |
[1,5,25,42,133,618,643,701,1962,8150,147458, 168459,356038,415870,536685,637757,1093612, 1207618,3368325,3470706,23400631,37621653] |