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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 10 |
| 5 | 41 |
| 6 | 46 |
| 7 | 277 |
| 8 | 566 |
| 9 | 1601 |
| 10 | 1834 |
| 11 | 18341 |
| 12 | 17802 |
| 13 | 213625 |
| 14 | 230870 |
| 15 | 225365 |
| 16 | 465790 |
| 17 | 7452641 |
| 18 | 8129874 |
| 19 | 146337733 |
[1,1,3,10,41,46,277,566,1601,1834,18341,17802, 213625,230870,225365,465790,7452641,8129874, 146337733] |