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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 9 |
| 5 | 13 |
| 6 | 54 |
| 7 | 384 |
| 8 | 596 |
| 9 | 7289 |
| 10 | 18136 |
| 11 | 226871 |
| 12 | 1577601 |
| 13 | 5240465 |
| 14 | 13389981 |
| 15 | 130707763 |
| 16 | 157598052 |
| 17 | 617834651 |
| 18 | 998713177 |
| 19 | 4596574856 |
[1,2,3,9,13,54,384,596,7289,18136,226871,1577601, 5240465,13389981,130707763,157598052,617834651, 998713177,4596574856] |