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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 1 |
| 5 | 3 |
| 6 | 9 |
| 7 | 23 |
| 8 | 73 |
| 9 | 239 |
| 10 | 601 |
| 11 | 4153 |
| 12 | 14191 |
| 13 | 114759 |
| 14 | 580339 |
| 15 | 5550888 |
| 16 | 46368603 |
| 17 | 562683992 |
| 18 | 5393792447 |
| 19 | 97221007962 |
| 20 | 1178726702163 |
| 21 | 29671069397702 |
| 22 | 489244079163479 |
[1,1,3,1,3,9,23,73,239,601,4153,14191,114759, 580339,5550888,46368603,562683992,5393792447, 97221007962,1178726702163,29671069397702, 489244079163479] |