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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 41 |
| 4 | 395 |
| 5 | 4503 |
| 6 | 68969 |
| 7 | 1205345 |
| 8 | 24831145 |
| 9 | 574932340 |
| 10 | 14936279962 |
| 11 | 427782949566 |
| 12 | 13426887958078 |
| 13 | 457622797727840 |
| 14 | 16842616079514468 |
| 15 | 665489067204502336 |
| 16 | 28102162931539093732 |
| 17 | 1262904299189373463930 |
| 18 | 60182778247311758955112 |
[1,7,41,395,4503,68969,1205345,24831145,574932340, 14936279962,427782949566,13426887958078, 457622797727840,16842616079514468, 665489067204502336,28102162931539093732, 1262904299189373463930,60182778247311758955112] |