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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 5 |
| 7 | 15 |
| 8 | 33 |
| 9 | 101 |
| 10 | 729 |
| 11 | 5159 |
| 12 | 33035 |
| 13 | 302287 |
| 14 | 3979621 |
| 15 | 62594669 |
| 16 | 1090041091 |
| 17 | 25034274381 |
| 18 | 742760513733 |
| 19 | 26752494041629 |
[1,1,1,1,1,5,15,33,101,729,5159,33035,302287, 3979621,62594669,1090041091,25034274381, 742760513733,26752494041629] |