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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 13 |
| 5 | 51 |
| 6 | 31 |
| 7 | 1653 |
| 8 | 6077 |
| 9 | 41779 |
| 10 | 638701 |
| 11 | 5158473 |
| 12 | 15616855 |
| 13 | 689190373 |
| 14 | 4459154883 |
| 15 | 59035926771 |
| 16 | 1195876420317 |
| 17 | 15970500617363 |
| 18 | 99735648719485 |
| 19 | 4555440147330105 |
| 20 | 42624771030616373 |
| 21 | 896478845515669809 |
| 22 | 21027550319473343163 |
| 23 | 399975004886038739435 |
[1,1,1,1,13,51,31,1653,6077,41779,638701,5158473, 15616855,689190373,4459154883,59035926771, 1195876420317,15970500617363,99735648719485, 4555440147330105,42624771030616373, 896478845515669809,21027550319473343163, 399975004886038739435] |