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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 17 |
| 5 | 70 |
| 6 | 349 |
| 7 | 2017 |
| 8 | 11253 |
| 9 | 58743 |
| 10 | 286327 |
| 11 | 1331630 |
| 12 | 6077344 |
| 13 | 27523597 |
| 14 | 126333667 |
| 15 | 587717372 |
| 16 | 2760990038 |
| 17 | 13033515692 |
| 18 | 61583867944 |
| 19 | 290639649211 |
| 20 | 1368090247852 |
| 21 | 6426462715392 |
| 22 | 30151737816899 |
| 23 | 141417395713905 |
[1,2,5,17,70,349,2017,11253,58743,286327,1331630, 6077344,27523597,126333667,587717372,2760990038, 13033515692,61583867944,290639649211, 1368090247852,6426462715392,30151737816899, 141417395713905] |