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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 2 |
| 6 | 2 |
| 7 | 4 |
| 8 | 12 |
| 9 | 39 |
| 10 | 71 |
| 11 | 83 |
| 12 | 484 |
| 13 | 1028 |
| 14 | 1447 |
| 15 | 9913 |
| 16 | 31542 |
| 17 | 526880 |
| 18 | 685669 |
| 19 | 1396494 |
| 20 | 1534902 |
| 21 | 2295194 |
| 22 | 9521643 |
| 23 | 9643315 |
| 24 | 42421746 |
| 25 | 183962859 |
| 26 | 553915624 |
| 27 | 557976754 |
| 28 | 6111180351 |
| 29 | 10671513549 |
| 30 | 61650520975 |
| 31 | 106532505646 |
[1,1,2,2,2,2,4,12,39,71,83,484,1028,1447,9913, 31542,526880,685669,1396494,1534902,2295194, 9521643,9643315,42421746,183962859,553915624, 557976754,6111180351,10671513549,61650520975, 106532505646] |