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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 5 |
| 6 | 16 |
| 7 | 66 |
| 8 | 343 |
| 9 | 2167 |
| 10 | 16193 |
| 11 | 140919 |
| 12 | 1414947 |
| 13 | 16258868 |
| 14 | 211935996 |
| 15 | 3105828560 |
| 16 | 50748310068 |
| 17 | 918138961643 |
| 18 | 18287966027343 |
| 19 | 399145502051200 |
| 20 | 9505803743367971 |
| 21 | 246064556796896554 |
| 22 | 6897674469134480653 |
| 23 | 208651954748397405264 |
| 24 | 6788671409470892058148 |
[1,1,1,2,5,16,66,343,2167,16193,140919,1414947, 16258868,211935996,3105828560,50748310068, 918138961643,18287966027343,399145502051200, 9505803743367971,246064556796896554, 6897674469134480653,208651954748397405264, 6788671409470892058148] |