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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 89 |
| 3 | 180 |
| 4 | 8009 |
| 5 | 16198 |
| 6 | 720721 |
| 7 | 1457640 |
| 8 | 64856881 |
| 9 | 131171402 |
| 10 | 5836398569 |
| 11 | 11803968540 |
| 12 | 525211014329 |
| 13 | 1062225997198 |
| 14 | 47263154891041 |
| 15 | 95588535779280 |
| 16 | 4253158729179361 |
| 17 | 8601905994138002 |
| 18 | 382737022471251449 |
| 19 | 774075950936640900 |
| 20 | 34442078863683451049 |
[1,2,89,180,8009,16198,720721,1457640,64856881, 131171402,5836398569,11803968540,525211014329, 1062225997198,47263154891041,95588535779280, 4253158729179361,8601905994138002, 382737022471251449,774075950936640900, 34442078863683451049] |